GET DIRECTORATE MATHEMATICS GRADE 4 DATE: ……………………. TOPIC: MULTIPLICATION CONCEPTS AND SKILLS WHICH MUST BE ACHIEVED At the end of the essons learners should be able to: • Understand multiplication as repeated addition and move on to the recognition of patterns in the multiplication table • Propose multiplication in rows and columns • Respond to the vocabulary used for multiplication • Use the appropriate symbols to interpret number sentences • Understand and practice that multiplication can be done in any order (the commutative law) • Reconcile and use the relationship between multiplication and multiples of a number • Recognize and use multiplication tables • Understand and use the connection between multiplication and doubling • Multiply a one-digit number by a two-digit number and vice versa • Multiply a two-digit number by a two-digit number • Use a variety of calculation techniques in multiplication • Recognize and solve multiplication problems RESOURCES: Sasol-Inzalo book. Textbooks, DBE Workbooks Day 1 Revision: Example –Rows and Columns The apples in the picture have been arranged in rows. There are 4 rows with 6 apples in each. Rows Apples 4 6 Multiples 6 6; 12; 18; 24 Repeated addition 6 + 6 + 6 + 6 = 24 Multiplication 4 rows x with 6 apples each = 24 apples 4 x 6 = 24 The apples may also be arranged in columns. There are 6 columns with 4 apples in each. Columns Apples 6 4 Multiples 4 4; 8; 12; 16; 20; 24 4 + 4 + 4 + 4 + 4+ 4= 24 Repeated addition Multiplication 6 columns with 4 apples each = 24 apples 6 x 4 =24 CLASS ACTIVITIY: Study the picture below. The first one has been completed. (a) There are 6 rows with 2 hearts in each row. (b) We can count in multiples of 2. (c) Multiples of 2 are 2; 4; 6; 8; 10; 12 (d) Write an addition number sentence: 2 + 2 + 2 + 2 + 2 + 2 =12 (e) Write a multiplication number sentence: 6 x 2 =12 (f) There are 2 columns with 6 hearts in each column. (g) We can count in multiples of 6. (h) Multiples of 6 are 6; 12 (i) Write an addition number sentence: 6 + 6 =12 (j) Write a multiplication number sentence: 2 x 6 =12 1. (a) There are ____ rows with ____ circles in each row. (b) We can count in multiples of ____. (c) Multiples of ____ are ____ (d) Write an addition number sentence: __________________ (e) Write a multiplication number sentence: __________________ (f) There are ____ columns with ____ circles in each column. (g) We can count in multiples of ____. (h) Multiples of ____ are ____ (i) Write an addition number sentence: __________________ (j) Write a multiplication number sentence: __________________ 2. (a) There are ____ rows with ____ triangles in each row. (b) We can count in multiples of ____. (c) Multiples of ____ are ____ (d) Write an addition number sentence: __________________ (e) Write a multiplication number sentence: __________________ (f) There are ____ columns with ____ triangles in each column. (g) We can count in multiples of ____. (h) Multiples of ____ are ____ (i) Write an addition number sentence: __________________ (j) Write a multiplication number sentence: __________________ 2 Grade 4 (draft) Multiplication 3. (a) (b) (c) (d) (e) (f) (g) (h) (i) (j) 4. There are ____ rows with ____ stars in each row. We can count in multiples of ____. Multiples of ____ are ____ Write an addition number sentence: __________________ Write a multiplication number sentence: __________________ There are ____ columns with ____ stars in each column. We can count in multiples of ____. Multiples of ____ are ____ Write an addition number sentence: __________________ Write a multiplication number sentence: __________________ Complete the following: (a) Draw 8 rows with 4 triangles in each. (b) We can count in multiples of ____. (c) Multiples of ____ are ____ (d) Write an addition number sentence: __________________ (e) Write a multiplication number sentence: __________________ (f) There are ____ columns with ____ triangles in each column. (g) We can count in multiples of ____. (h) Multiples of ____ are ____ (i) Write an addition number sentence: __________________ (j) Write a multiplication number sentence: __________________ 3 Grade 4 (draft) Multiplication Solve 5. Marco has a vegetable garden. He plants 7 rows of cabbage with 5 cabbage plants in each. Sue-Ann has a garden as well. She plants 5 rows of cabbage with 7 cabbage plants in each. (a) Draw a sketch of Marco’s garden. (You may use circles to represent cabbages) Marco’s garden (b) Write an addition number sentence to show the total cabbages in his garden. _______________________________________ (c) Write a multiplication number sentence to show the total cabbages in his garden. _______________________________________ (d) Draw a sketch of Sue-Ann’s garden. (you may use circles to represent cabbages) Sue-Ann ‘s garden (e) Write an addition number sentence to show the total cabbages in her garden. _______________________________________ (f) Write a multiplication number sentence to show the total cabbages in her garden. _______________________________________ (g) Who owns the most plans? _______________________________________ HOMEWORK: 6. (a) There are ____ rows with ____ ladybugs in each row. (b) We can count in multiples of ____. (c) Multiples of ____ are ____ (d) Write an addition number sentence: __________________ (e) Write a multiplication number sentence: __________________ (f) There are ____ columns with ____ ladybugs in each column. (g) We can count in multiples of ____. (h) Multiples of ____ are ____ (i) Write an addition number sentence: __________________ (j) Write a multiplication number sentence: __________________ 4 Grade 4 (draft) Multiplication 7. During a school concert Rushen counted 9 columns with 4 cars in each, in the parking area. (a) Draw a sketch of the parking area. (You may use circles to represent cars) (b) Write two addition number sentences to show the cars. ______________________________________ ______________________________________ (c) Write two multiplication number sentences to show the cars. ______________________________________ ______________________________________ Day 2 Revision: Examples- Grouping and Number lines Objects can be grouped, making it easier for us to count it. Study the picture below. 5 x 3 = 15 Count: 3 + 3 + 3 + 3 + 3 = 15 (Repeated Addition) (a) We place the stars in 5 groups of 3. (b) We can count the star in multiples of 3: 3; 6; 9; 12; 15. (c) Using repeated addition, write an addition number sentence: 3 + 3 + 3 + 3 + 3 + 3 = 15. (d) We can write 5 groups of 3 as a multiplication number sentence as: 5 x 3 = 15. (e) Using a number sentence, we can calculate 5 groups of 3: 5 x 3 = 15 5 Grade 4 (draft) Multiplication CLASS ACTIVITIY: Complete the activity in your writing book. The first one has been completed for you. (a) There are 8 groups of 2 leaves in each group. (b) We can count in multiples of 2: 2; 4; 6; 8; 10; 12; 14; 16 (c) Write an addition number sentence: 2 + 2 + 2 + 2 + 2 + 2 + 2 + 2 = 16 (d) Write a multiplication number sentence: 8 x 2 = 16 (e) Show 8 groups of 2 in a number sentence on a number line: 8 x 2 = 16 (f) How many leaves are there altogether? 16 leaves 1. (a) There are _____ groups of _____ flowers in each group. (b) We can count in multiples of ____; _______________________________ (c) Write an addition number sentence: ________________________________ (d) Write a multiplication number sentence: _________________________ (e) Show _____ groups of _____ in a number sentence on a number line: (f) How many flowers are there altogether? _____________________________ 2. (a) There are _____ groups of _____ red dots in each group. (b) We can count in multiples of ____; (c) _______________________________ (d) Write an addition number sentence: ________________________________ (e) Write a multiplication number sentence: _________________________ (f) Show _____ groups of _____ in a number sentence on a number line: (g) How many red dots altogether? ___________________________ 6 Grade 4 (draft) Multiplication 3. Draw 4 groups with 7 triangles in each group. (a) We can count in multiples of ____; _______________________________ (b) Write an addition number sentence: ________________________________ (c) Write a multiplication number sentence: _________________________ (d) Show _____ groups of _____ in a number sentence on a number line: (e) How many triangles altogether?? ______________________________________ 4. Keesha buys 5 packets with 8 sweets in each. (a) Draw the ____ packets with _____ sweets in each. (b) We can count in multiples of ____; _______________________________ (c) Write an addition number sentence: ________________________________ (d) Write a multiplication number sentence: _________________________ (e) Show _____ groups of _____ in a number sentence on a number line: (f) How many sweets altogether?? ______________________________________ Homework 6. (a) There are _____ cakes with ____ candles on each cake. (b) We can count in multiples of ____; _______________________________ (c) Write an addition number sentence: ________________________________ (d) Write a multiplication number sentence: _________________________ (e) Show _____ groups of _____ in a number sentence on a number line (f) How many candles altogether? _____________________________ 7 Grade 4 (draft) Multiplication 7. Thuli collects old coins. She packs these in 6 groups with 7 coins in each group. (a) Draw Thuli’s coin collection. ((You may use circles to represent the coins). (b) Write an addition number sentence: ________________________________ (c) Write a multiplication number sentence: _________________________ (d) Show _____ groups of _____ in a number sentence on a number line (e) How many coins altogether? _____________________________ (f) Day 3 Multiplication Counting takes a lot of time, especially when there are many objects. For instance, it may take a lot of time to count all the squares shown on the right. A quicker way: • is to add 16 repeatedly: 16 + 16 + 16 + ... • But if you can calculate 18 × 16, it is even quicker! • To be able to calculate something like 18 × 16, you need to • know some multiplication facts, such as 10 × 6 = 60, 8 × 6 = 48, 10 × 10 = 100 and 8 × 10 = 80. In this unit you will learn many facts like these. 1. How many squares are shown on this page? 2. Compare your answer with that of a classmate. 8 Grade 4 (draft) Multiplication Count objects (a) How many bananas are there in one bunch? (b) How many bananas are there in five bunches? (c) How many bananas are there in ten bunches? (d) How many bananas are there in nine bunches? (e) How many bananas are there in seven bunches? (f) How many bananas are there in six bunches? What did you notice? • 3 is added every time. • You have counted in multiples of 3. • 1 bunch has 3 bananas. • It can be written using symbols: 1 x 3 = 3 • 5 bunches of 3 is 15: 5 x 3 = 15 • 10 bunches of 3 is 30: 10 x 3 = 30 • 9 bunches of 3 is 27: 9 x 3 = 27 • 7 bunches of 3 is 21: 7 x 3 = 21 • 6 bunches of 3 is 18: 6 x 3 = 18 CLASS ACTIVITIY Complete the following activity. 1. Use the numbers in the counting pattern that you wrote for question 3 to say how much each of the following is. (a) 6 x 3 2. (b) 7 x 3 How much is each of the following? (a) 10 x 3 (b) 9 x 3 (e) 2 x 3 (f) 3 x 3 (c) 8 x 3 (d) 4 x 3 (c)7 x 3 (g) 6 x 3 (d) 5 x 3 (h) 4 x 3 You multiplied by 3 every time. This is called the 3-multipliation table. 3. Rewrite the table below as the 3-multipliation table. x 1 2 3 4 3 3 6 9 12 5 6 7 8 9 10 9 Grade 4 (draft) Multiplication 4. Using your knowledge of the 3-multipliation table, complete the exercise below. Start with the multiplication first before add or subtracting. Example: 4x3+6x3 7x3–5x3 = 12 + 18 = 21 - = 30 = 6 (a) 5 x 3 + 3 x 3 (c) 6 x 3 + 6 x 3 (e) 9 x 3 – 4 x 3 15 (b) 12 x 3 (d) 10 x 3 – 4 x 3 (f) 4 x 3 +5 x 3 Homework 5. How many bananas are? (a) 3 bunches of 5 bananas? ________ (b) 5 bunches of 3 bananas? _____________ (b) What have you noticed about 3 x 5 and5 x 3? ____________________________________________ Day 4 Learn more multiplication facts 1. 2. 3. (a) How many bananas are there in ten bunches? (b) How many bananas are there in nine bunches? (c) How many bananas are there in eight bunches? (d) How many bananas are there in seven bunches? Complete thenumber pattern, by writing the first 20 numbers in the sequence below. 4 ; 8 ; 12 ; 16 ; __________________________________________________________________________ Using the numbers you wrote in number 2 complete the following. (a) 6 x 4 = (b) 7 x 4 = (c) 8 x 4 = (d) 4 x 4 = (e) 9 x 4 = (f) 10 x 4 = 10 Grade 4 (draft) Multiplication 4. Complete the four times table below. 5. 6. x 1 2 3 4 4 4 8 12 16 5 6 7 8 9 10 (a) How many bunches of 4 make 20 bananas? b) How many bunches of 4 make 28 bananas? (c) How many bunches of 3 make 42 bananas? (d) How many bunches of 3 make 36 bananas? (e) How many bananas should be in each bunch so that 5 bunches are 15 bananas? (f) How many bananas should be in each bunch so that 7 bunches are 28 bananas? Use your knowledge of the following multiplication facts to complete the number sentences. Use the examples below to guide you. 7x3–5x3 4x3+6x3 = 12 + 18 = 21 - = 30 = 6 (a) 5 x 4 + 4 x 4 (c) 6 x 4 + 6 x 4 (e) 4 x 9 – 4 x 4 15 (b)10 x 4 – 4 x 4 (d) 12 x 4 (f) 4 x 4 + 4 x 5 Homework 7. Complete the five times table below. 8. x 1 2 3 4 5 5 10 15 20 5 6 7 How much is each of the following? (a) 10 x 5 (b) 9 x 5 (d) 5 x 5 (e) 2 x5 (g) 8 x 5 (h) 3 x 5 8 9 10 (c) 7 x 5 (f) 6 x 5 (i) 4 x 5 11 Grade 4 (draft) Multiplication 9. (a) How many bananas are there in six bunches of five bananas each? (b) How many bananas are there in ten bunches of five bananas each? (c) How many bananas are there in nine bunches of five bananas each? (d) How many bananas are there in eight bunches of five bananas each? (e) How many bananas are there in seven bunches of five bananas each? 10. 11. Copy and complete the ten times table. x 1 2 10 10 20 4 5 6 7 Copy and complete the six times table. If you wish, you may use the three times table that you made earlier to help you. x 1 2 3 4 5 6 7 6 12. 3 8 9 10 8 9 10 24 There are six bottles of juice in one pack. (a) How many bottles are there in 8 packs? (b) How many bottles are there in 9 packs? Day 5 Revise the 3, 4, 5, 6 and 10 multiplication tables Complete without looking at the 3 times, 4 times, 5 times, 10 times and 6 times tables that you learnt earlier. 12 Grade 4 (draft) Multiplication CLASS ACTIVITIY Multiplication with 7, 8 and 9 1. Make a copy of the table and fill in the facts you already know. 2. How much is each of the following? To find the answers, you may count in nines if you wish, or you can use different methods. (a) 9 + 9 + 9 + 9 + 9 + 9 (b) 9 + 9 + 9 + 9 + 9 + 9 + 9 (c) 9 + 9 + 9 + 9 + 9 + 9 + 9 + 9 (d) 9 + 9 + 9 + 9 + 9 + 9 + 9 + 9 + 9 3. There are 7 rows with 10 dots each in this diagram. Which of the following multiplication facts can you use? to know how many dots there are in the diagram, altogether? 4. (a) 7 x 7 = 49 (b) 7 x 8 = 56 (c) 7 x 9 =64 (d) 7 x 10 = 70 Use the multiplication facts that you know to say how many squares there are in each of the diagrams below. (a) (b) (c) (d) 13 Grade 4 (draft) Multiplication Homework 5. 6. 7. Copy and complete the table. Write a multiplicatrion number sentence for each of the problems below. (The first one has been completed for you). (a) 9 apples at R7 each • 9 x 7 = R63 (c) 7 pencils at R8 each (b) 8 cans of juice at R9 each (e) 6 oranges at R8 each (f) pears at R8 each (d) pens at R9 each Use your knowledge of multiplication facts by writing number sentences to solve problems. (The first one has been completed for you). (a) How many groups of 4 are equal to 24? 5 x 4 = 20 5 x 4 = 20 (b) How many rows of 6 are equal to 24? (c) How many rows of 7 oranges are equal to 21oranges? (d) How many columns of 9 are equal to 27? (e) How many packets of 8 sweets each are equal to 40 sweets? 14 Grade 4 (draft) Multiplication Day 6 Presentation: Learning to multiply with bigger numbers (Educators and learners) 1. It is important to remember the multiplication facts that you have learnt. Each step helps with the next. Let us check what you already know and how it can be used to learn more. X1 (a) (b) (c) (d) (e) (f) (g) 4x1=4 6x1= 7x1= 2x1= 5x1= 9x1= 10 x 1 = X 10 4 x 10 = 40 6 x 10 = 7 x 10 = 2 x 10 = 5 x 10 = 9 x 10 = 10 x 10 = X2 4x2=8 6x2= 7x2= 2x2= 5x2= 9x2= 10 x 2 = X 20 4 x 20 = 80 6 x 20 = 7 x 20 = 2 x 20 5 x 20 = 9 x 20 = 10 x 20 = Class Activity 2. Complete the table below. (The first one has been completed for you). (a) 4 x 1 = 4 en 4 x 10 = 40. X3 X 30 X6 X 60 (a) 4 x 3 = 12 4 x 30 = 120 4 x 6 = 24 4 x 60 = 240 (b) 6x3= 6 x 30 = 6x6= 6 x 60 = (c) 7x3= 7 x 30 = 7x6= 7 x 60 = (d) 2x3= 2 x 30 = 2x6= 2 x 60 (e) 5x3= 5 x 30 = 5x6= 5 x 60 = (f) 9x3= 9 x 30 = 9x6= 9 x 60 = (g) 10 x 3 = 10 x 30 = 10 x 6 = 10 x 60 = 3. Complete the table below. (The first one has been completed for you). x4 x 40 x8 x 80 (a) 4 x 4 = 16 4 x 40 = 160 4 x 8 = 32 4 x 80 = 320 (b) 6x4= 6 x 40 = 6x8= 6 x 80 = (c) 7x4= 7 x 40 = 7x8= 7 x 80 = (d) 2x4= 2 x 40 = 2x8= 2 x 80 (e) 5x4= 5 x 40 = 5x8= 5 x 80 = (f) 9x4= 9 x 40 = 9x8= 9 x 80 = (g) 10 x 4 = 10 x 40 = 10 x 8 = 10 x 80 = 15 Grade 4 (draft) Multiplication 4. Complete the table below. (The first one has been completed for you). x5 x 50 x 70 x 90 (a) 4 x 5 = 20 4 x 50 = 200 4 x 70 = 28 4 x 90 = 360 (b) 6x5= 6 x 50 = 6 x 70 = 6 x 80 = (c) 7x5= 7 x 50 = 7 x 70 = 7 x 80 = (d) 2x5= 2 x 50 = 2 x 70 = 2 x 80 (e) 5x5= 5 x 50 = 5 x 70 = 5 x 80 = (f) 9x5= 9 x 50 = 9 x 70 = 9 x 80 = (g) 10 x 5 = 10 x 50 = 10 x 70 = 10 x 80 = 5. Complete the table below. (The first one has been completed for you). (a) 50 x 20 = 100 (d) 40 x 6 = (g) 70 x 5 = (j) 20 x 30 = (b) 40 x 30 = 120 (e) 80 x 2 = (h) 9 x 20 = (k) 10 x 80 = (c) 7 x 40 = (f) 90 x 3 = (i) 1 x 70 = (l) 60 x 10 = Homework 6. Complete the number sentences below. (a) 30 x ___ = 270 (d) ___ x 40 = 120 (g) 50 x ___ = 600 (j) 30 x ___ = 210 (b) 450 = 50 x ___ (e) 30 x ___ = 5 x 30 (h) 400 = 40 x ___ (k) 40 x ___ = 360 (c) 120 = ___ x 20 (f) 4 x ___ 8 = 8 x 20 (i) 800 = 40 x ___ (l) 280 = 40 x ___ 7. Mia sells pancakes at R7 each. Calculate the costs of the pancakes. Total pancakes Cost in Rand 1 R7 2 R14 3 4 5 6 7 8 9 Total pancakes Cost in Rand 10 R70 20 R140 30 40 50 60 70 80 90 8. (a) 3 x 20 + 5 x 20 (b)5 x 30 + 4 x 30 (d) 9 x 40 + 5 x 40 (e) 6 x 30 (c) 40 x 4 + 50 x 6 16 Grade 4 (draft) Multiplication Day 7 A. Multiplication in reverse Using multiplication facts to solve problems A. David paid R63 for 7 packets of sweets. How much did each packet cost? B. How many breads can Musi buy for R48 when each bread costs R6? The table on the right can help you solve A and B. Look at the table. Note that the numbers 48 and 63 are coloured in. Now use the table to find the answers to the following questions. (a) How many sixes make up 48? (b) 7 × which number? = 63 Problem A • 63 = 7 x ___; OR • How many 7s is equal to 63; OR • 7 x ___ = 63 On the table we see that: • 63 = 7 x 9. • 7 x 9 = 63 When we calculate in reverse(backwards), we find that we are dividing to find the answer: 63 ÷ 7 = 9 Problem B • 48 = 6x ___; OR • How many 6s is equal to 48; OR • __ X 6 = 48 48 ÷ 6 = 8 On the table we see that: • 48= 6 x 8. • 6x 8 = 48 17 Grade 4 (draft) Multiplication B. Multiplying in steps A flow diagram consists of three parts: • the input numbers, for example 4, 3 and 2 in the flow diagrams below • the operator(s), for example × 6 in question 1, and × 2 and × 3 in question 2 • the output numbers, for example the number 24 in question 2. In question 2, the number 8 is an output number for the first flow diagram, and it is also an input number for the second flow diagram. 1. What are the output numbers at (a), (b) and (c)? Class Activity Complete the following in your writing book 1. Calculate the missing number in each of the following and write the division number sentence. (The first one has been completed for you.) Multiplication Division number sentence number sentence (a) 4 x 6 = 24 24 ÷ 4 = 6 (b) ___ x 8 = 32 (c) 27 = 3 x ___ (d) ___ x 9 = 36 (e) 3 x ___ = 18 (f) 49 = ___ x 7 (g) 8 x ___ = 56 (h) ___ x 8 = 64 (i) 63 = 7 x ___ (j) ___ x 6 = 60 (k) 6 x ___ = 54 (l) 35 = ___ x 5 18 Grade 4 (draft) Multiplication 2. Calculate the missing number in each of the following and write the multiplication number sentence. (The first one has been completed for you.) Division Multiplication number sentence number sentence (a) 10 ÷ 2 = 5 5 x 2 = 10 (b) 9÷3= (c) 12 ÷ 2 = (d) 12 ÷ 3 = (e) 12 ÷ 4 = (f) 20 ÷ 4 = (g) 10 ÷ 5 = (h) 25 ÷ 5 = 3. Write a multiplication and disvision number sentence to solve the following problems. (a) One mango costs R8. How many mangoes can Christelle buy with R32? (b) Emma paid R45 for five bars of soap. What was the price of one bar of soap? 4. Complete the following glow diagram. Number sentence: 4 x 2 = 8; 8 x 3 = 24 4 x 2 x 3 = 24 Homework 5. Write a multiplication and disvision number sentence to solve the following problems. Division Multiplication Division Multiplication number number Number number sentence sentence sentence sentence (a) 63 ÷ 7 = 9 7 x 9 = 63 (g) 90 ÷ 10 = (b) 35 ÷ 5 = (h) 81 ÷ 9 = (c) 64 ÷ 8 (i) 45 ÷ 5 = (d) 56 ÷ 8 = (j) 28 ÷ 7 = (e) 100 ÷ 10 = (k) 49 ÷ 7 = (f) 90 ÷ 9 = (l) 72 ÷ 9 = 6. Complete the following glow diagram. 19 Grade 4 (draft) Multiplication 7. Complete the following problem by writing a number sentence first. Mrs Jacobs bakes biscuits. She bakes 6 rows of biscuits on a tray. There are four biscuits in each row. How many biscuits has she baked if she makes 5 trays? 8. Complete the following problem by writing a number sentence first. A Teacher has 35 elastic bands. Learners are sitting in 5 equal groups. How many elastic bands will each group receive if it shared amongst the learners? Day 8 Multiplication with 3 or more numbers Example 1 (a) Calculate 68 x7. (b) Break up 68 into 60 and 8 Example 2 If 3 or more numbers are multiplied with each other, these numbers can be rearranged with the answer remaining the same. (a) 2x5x7 2x7x5 = 10 x 7 = 14 x 5 = 70 = 70 (b) 25 x 7 x 4 can be calculated easier: 25 x 4 x 7 = 100 x 7 = 700 20 Grade 4 (draft) Multiplication Class Activity 1. Use example 1 to assist you to complete the following in your writing book. (a) 2. 36 x 6 (c) 8 x 39 (d) 9 x 63 Use example 2 to assist you to complete the following (a) 2x7x5 (d) 12 x 2 x 5 3. (b) 78 x 4 (b) 25 x 7 x 4 (c) 4 x 47 x 5 (e) 10 x 17 x 5 (f) 2 x 7 x 55 Mrs Mentoor bought 2 bags of bananas with 3 bunches of 5 bananas in each bag. (a) How many bananas did she buy? (b) Write down how you can calculate the number of bananas, without actually counting them, but by multiplication. (c) You can check your calculation by counting the bananas. 4. Mr Nene bought 3 bags of bananas with 5 bunches of 2 bananas in each bag. (a) How many bananas did he buy? (b) Write down how you can calculate the number of bananas, without actually counting them, but by multiplication. (c) You can check your calculation by counting the bananas. Homework 5. 6. 7. How much is each of the following? (a) 7 x 60 (b) 4 x 80 (c) 6 x 70 Calculate the missing number in each number sentence. (a) ___ x 80 = 320 (b) ___ x 70 = 420 (c) ___ x 50 = 450 (d) 9 x 50 (d) ___ x 60 = 420 (a) How many books at R80 each can you buy with R320? (b) How many books at R40 each can you buy with R320? 21 Grade 4 (draft) Multiplication Day 9 Revision 1. Complete the following flow diagrams. 2. Complete the following flow diagrams by calculating the input number. 3. Copy this table and write your answers for question 1 in it. NUmber 7 9 10 6 3 Number x 7 70 35 28 63 42 22 Grade 4 (draft) Multiplication Multiplying with larger numbers Example 1 17 x 7 can be calculated by showing It visually, as shown in the diagram on the right. There are 17 columns and 7 rows. 17 columns x x x x x x x x x x x x x x x x x x x x x x x x x x x x x x x x x x x x x x x x x x x x x x x x x x x x x x x x x x x x x x x x x x x x x x x x x x x x x x x x x x x x x x x x x x x x x x x x x x x x x x x x x x x x x x x x x x x x x x x 10 columns 7 rows + 7 columns x x x x x x x x x x x x x x x x x x x x x x x x x x x x x x x x x x x x x x x x x x x x x x x x x x x x x x x x x x x x x x x x x x x x x x x x x x x x x x x x x x x x x x x x x x x x x x x x x x x x x x x x x x x x x x x x x x x x x x x 7 rows We can divide the diagram so that we have 10 columns + 7 columns and 7 rows each. 10 columns x 7 rows + 7 columns x 7 rows = 70 + 49 = 119 altogether Example 2 46 x 37 may be calculated using the grid or area model. • Start by breaking each number into each place values • 46 = 40 + 6 en 37 = 30 + 7 • Draw a grid. • Fill in the numbers as indicated on the right. • Multiply the numbers. • Add the the shaded answers/ products together 30 + 7 40 x 30 = 1 200 40 x 7 = 280 6 x 30 = 180 6 x 7 = 42 46 x 37 = 1 200 + 280 + 180 + 42 = 1000 + 200 + 200 + 80 + 100 + 80 + 40 + 2 = 1 702 23 Grade 4 (draft) Multiplication Example 3 64 x 78 may also be calculated as Follows: • Start by breaking each number into each place values • 64 = (60 + 4) en 78 = (70 + 8) • Use brackets when breaking up numbers • Multiply each of the of values of the first numbers with values of the second number. • Add all the products together. Class activity 1. Calculate the following using any strategy above? (a) 43 × 38 (b) 37 × 28 (c) 32 × 57 (d) 64 × 57 2. Determine the total cost of each of the following. (a) 86 boxes of cereal at R57 each (b) 46 sets of cutlery at R83 for one set (c) 53 sets of glasses at R47 for one set (d) 72 pairs of socks at R46 for one pair (e) 64 T-shirts at R89 for one T-shirt (a) (f) 78 caps at R79 for one cap Homework 3. Calculate. (a) 44 x 98 (b)34 x 19 (c) 47 x 17 (d) 38 x 23 4. (a) One diary costs R39. How much will 48 diaries cost? (b) If one bread roll costs 55c, how much will you pay for 36 bread rolls? (c) There are 24 hours in a day. How many hours are there in a week? (d) There are 60 minutes in an hour. How many minutes are there in 24 hours? 24 Grade 4 (draft) Multiplication Day 10 1. Study the picture below and answer the questions that follow Complete the missing labels for X and Y (X) (Y) 2. Use the diagram in number 1. Complete the table below by writing down the letters and the answers next to it. The stars in the picture have been arranged in ____(a)____ rows with ____(b)____ in each. Multiples (e) (f) Repeated addition (i) Multiplication number sentence (k) The stars may also be arranged in columns. There are ____(c)____ columns with ____(d)____ in each. Multiples (g) (h) Repeated addition (j) Multiplication number sentence (l) (3) (a) There are ____ rows with ____ triangles in each row. (b) We can count in multiples of ____. (c) Multiples of ____ are ____ (d) Write an addition number sentence: __________________ (e) Write a multiplication number sentence: __________________ (f) There are ____ columns with ____ triangles in each column. (g) We can count in multiples of ____. (h) Multiples of ____ are ____ (i) Write an addition number sentence: __________________ (j) Write a multiplication number sentence: __________________ 25 Grade 4 (draft) Multiplication 4. You have learnt that all the objects in the groups are arranged equally. Look at the following diagram and arrange these into equal rows and columns. Answer the questions that follow. A _________ B _________ C_________ A Groups x B = C Objects in Total number each group of objects (a) There are ____ rows with ____ circles in each row. (b) We can count in multiples of ____. (c) Multiples of ____ are ____ (d) Write an addition number sentence: __________________ (e) Write a multiplication number sentence: __________________ (f) There are ____ columns with ____ circles in each column. (g) We can count in multiples of ____. (h) Multiples of ____ are ____ (i) Write an addition number sentence: __________________ (j) Write a multiplication number sentence: __________________ 5. (a) There are ____ rows with ____ squares in each row. (b) We can count in multiples of ____. (c) Multiples of ____ are ____ (d) Write an addition number sentence: __________________ (e) Write a multiplication number sentence: __________________ (f) There are ____ columns with ____ squares in each column. (g) We can count in multiples of ____. (h) Multiples of ____ are ____ (i) Write an addition number sentence: __________________ (j) Write a multiplication number sentence: __________________ 26 Grade 4 (draft) Multiplication 6. (a) There are _____ rows of _____ circles each row. (b) We can count in multiples of ____;_ ______________________________ (c) Write an addition number sentence: ________________________________ (d) Write a multiplication number sentence: _________________________ (e) Show _____ groups of _____ in a number sentence on a number line: 7. Use the diagram in number 6 to complete the questions below (a) (b) (c) (d) (e) There are _____ columns of _____ circles each column. We can count in multiples of ____; _______________________________ Write an addition number sentence: ________________________________ Write a multiplication number sentence: _________________________ Show _____ groups of _____ in a number sentence on a number line: 8. Karen buys 5 bags of flour to make cookies. Each bag costs R7. Karen also buys one bag of chocolate chips for R3. How much did Karen spend at the market? (a) Figure out how much Karen spent on the flour by drawing the rows and columns of the problem above. (b) Karen can count in multiples of ____; _______________________________ (c) Write an addition number sentence: ________________________________ (d) Write a multiplication number sentence: _________________________ (e) (Show _____ groups of _____ in a number sentence on a number line: 9. Rewrite the table below as the 6-multipliation table. x 1 2 3 4 5 6 7 8 9 10 6 6 12 (a) (b) (c) (d) (e) (f) (g) (h) 27 Grade 4 (draft) Multiplication 10. Rewrite the table below as the 5-multipliation table. x 1 2 3 4 6 8 10 5 5 10 15 20 30 (a) (b) 11. Rewrite the table below as the 8-multipliation table. x 1 2 5 10 12 8 8 16 (a) (b) (c) 12. Use the numbers in the counting pattern that you wrote for question 10 AND 12 to say how much each of the following is. (a) 6 x 6 (b) 7 x 6 (c) 8 x 6 (d) 4 x 6 (e) 2 x 8 (f) 3 x8 (g) 7 x 8 (h) 11 x 8 13. Using your knowledge of the 5-multipliation table, complete the exercise below. Start with the multiplication first before add or subtracting. Example: 7x3–5x3 4x3+6x3 14. = 12 + 18 = 21 - = 30 = 6 15 (a) 5x5+3x5 (b) 12 x 5 (d) 9x5–4x5 (e) 10 x 5 – 7 x 5 (c) 6 x 5 + 9 x 5 (f) 4 x 8 +5 x 5 Multiply the following using the example on the right. (b) 27 x 8 (b) 43 x 5 (c) 6 x 59 (d) 2 x 88 28 Grade 4 (draft) Multiplication 15. Multiply the following using the example below. 2x5x7 2x7x5 =10 x 7 =14 x 5 = 70 = 70 (a) 8 x 6 x 5 (d) 15 x 8 x 6 (b) 25 x 5 x 2 (c) 9 x 3 x 5 (e) 11 x 6 x 5 (f) 10 x 7 x 5 16. What are the output numbers at (a), (b) and (c)? 17. What are the numbers at (a), (b), (c) and (d)? 18. Write the numbers that are missing below. 19. Complete the following number sentences. 20. (a) 7 × . . . = 56 (b) . . . × 9 = 27 (c) 33 = 3 × . . . (d) . . . × 8 = 48 (e) 5 × . . . = 25 (f) 72 = . . . × 8 (a) One diary costs R39. How much will 8 diaries cost? (b) If one bread roll costs 55c, how much will you pay for a half dozen? (c) There are 24 hours in a day. How many hours are there in a week? (d) There are 60 minutes in an hour. How many minutes are there in 24 hours? 29 Grade 4 (draft) Multiplication DAY 1: MEMORANDUM 1 (a) (b) (c) (d) (e) (f) (g) (h) (i) (j) 3 (a) (b) (c) (d) (e) (f) (g) (h) (i) (j) 5 (a) 3 rows; 10 circles 10 (10): 10; 20; 30 10 + 10 + 10 =30 3 x 10 =30 10 columns; 3 circles 3 (3): 3 ; 6 ; 9 ;12 ;15 ; 18 ; 21 ; 24 ; 27 ; 30 3+3+3+3+3+3+3+3+3+3 =30 3 x 10 =30 7 rows; 5 stars 5 (5): 5; 10; 15; 20; 25; 30; 35 5 + 5+ 5 + 5 +5 + 5+ 5 =35 7 x 5=35 5 columns; 7 stars 7 (7): 7 ; 14 ; 21 ;28 ;35 7 + 7 + 7 + 7 + 7 =35 5 x 7 =35 Marco’s garden 2 (a) (b) (c) (d) (e) (f) (g) (h) 5 rows; 8 triangles 8 (8): 8; 16; 24; 32; 40 8+ 8 + 8 + 8 + 8 =40 5 x 8 =20 8 columns; 5 triangles 5 5; 10; 15; 20; 25; 30; 35; 40 (i) 5 + 5+ 5 + 5 +5 + 5+ 5 + 5 =40 (j) 8 x 5=20 4 (a) (b) (c) (d) (e) (f) (g) (h) (i) (j) 8 rows; 4 triangles 4 (4): 4; 8;12; 16; 20; 24; 28; 32 4 + 4 + 4 + 4 + 4 + 4 + 4 + 4 =32 8 x 4 =32 4 columns; 8 triangles 8 (8) 8; 16; 24; 32 8 + 8 + 8 + 8 =32 4 x 8=20 Sue-Ann’s garden (d) (b) 5 + 5 + 5 + 5 + 5 + 5 + 5 = 35 (e) (f) (c) 7 x 5 =35 (g) 7 + 7 + 7 + 7 + 7 = 35 5 x7 =35 Both have 35 cabbages 30 Grade 4 (draft) Multiplication Homework 6 (a) (b) (c) (d) (e) (f) (g) (h) (i) (j) 3 rows; 8 ladybugs 8 (8): 8; 16; 24 8 + 8 + 8 = 24 3 x 8 =24 8 columns; 3 ladybugs 3 (3): 3; 6; 9;12;15; 18; 21 24 3 + 3 + 3 + 3 + 3 + 3 + 3 + 3 =30 8 x 3 =24 7 (a) (b) 4 + 4 + 4 + 4 + 4 + 4 + 4 + 4 + 4 = 36 (c) 9 x 4 = 36 4 x 9 = 36 DAY 2: MEMORANDUM CLASS ACTIVITY 1 (a) (b) (c) (d) (e) (f) 8 groups; 5 flowers 5 (5): 5; 10; 15; 20; 25; 30; 35; 40 5 + 5+ 5 + 5 +5 + 5+ 5+ 5 =40 8 x 5 =40 2 (a) (b) (c) (d) (e) 6 groups; 6 circles (6): 6; 12; 18; 24; 30; 36 6 + 6 + 6 + 6 + 6+ 6 =36 6 x 6 = 36 3. (b) (c) (d) (a) (7): 7; 14; 21; 28 7 + 7 + 7 + 7 = 28 4 x 7 = 28 31 Grade 4 (draft) Multiplication (e) (f) 4. (b) (b) (d) (e) 28 triangles (a) (8): 8; 16; 24; 32; 40 8 + 8 + 8 + 8 + 8 = 40_ 5 x 8 =40 (f) 40 sweets 5. (a) (b) 4 cakes; 7 candles (c) (7): 7; 14; 21; 28 7 + 7 + 7 + 7 = 28 (d) (e) 4 x 7 =28 (f) 6. (b) (c) (c) 28 candles (a) 7_+ 7 + 7 + 7 + 7 + 7 = 42_ 7x 6 = 28_ 6 + 6 + 6 + 6 + 6+ 6 =36 (d) (e) 42 coins DAY 3: MEMORANDUM 1. (a) 3 bananas (b) 15 bananas (c) 15 bananas (d) 30 bananas (e) 27 bananas (f) 21 bananas 32 Grade 4 (draft) Multiplication 2. (a) 18 (b) 21 (c) 24 (d) 12 (b) 27 (f) 9 (c) 21 (g) 18 (d) 15 (h) 12 3. (a) 30 (e)6 4. x 1 2 3 4 5 6 7 8 9 10 3 3 6 9 12 15 18 21 24 27 30 5. (a) 15 + 9 = 24 (b) 36 (d) 30 - 12 = 18 (e) 27 – 12 =15 6. (15 bananas (c) 18 + 9 = 27 (f) 12 + 15 = 27 (b) 15 bananas (c) answer remains the same DAY 4: MEMORANDUM 1. (a)40 2. 3. (b) 36 (c) 32 (d) 28 4 ; 8 ; 12 ; 16 ; 20 ; 24 ; 28 ; 32 ; 36 ; 40 ; 44 ; 48 ; 52 ; 56 ; 60 ; 64 ; 68 ; 72 ; 76 ; 80 (a) 24 (b) 28 (c) 32 (d) 16 (e) 36 (f) 40 4. x 1 2 3 4 5 6 7 8 9 10 4 4 8 12 16 20 24 28 32 36 40 5. (a) 5 (d) 12 (b) 7 (e) 3 (c) 14 (f) 4 6. (a) 20 + 16 = 36 (d) 48 (b) 40 – 14 = 26 (e) 36 -16 = 20 (c) 24 + 24 = 48 (f) 16 + 20 = 36 7. x 1 2 3 4 5 6 7 8 9 10 33 Grade 4 (draft) Multiplication 5 8. 9. 5 10 15 20 25 (a) 50 (b) 45 (c) 35 (g) 40 (h) 15 (i) 20 (b) 50 (c) 45 (a) 30 30 35 40 45 (d) 25 (e) 10 (d) 40 (e) 35 50 (f) 30 10. x 1 2 3 4 5 6 7 8 9 10 10 10 20 30 40 50 60 70 80 90 100 x 1 2 3 4 5 6 7 8 9 10 6 6 12 18 24 30 36 42 48 54 90 11. 12. (a) 48 (b) 54 DAY 5: MEMORANDUM Revision x 10 5 3 6 4 2 20 10 6 12 8 4 40 20 12 24 16 8 80 40 24 48 23 3 30 15 9 18 12 6 60 30 18 36 24 7 70 35 21 42 28 5 50 25 15 30 20 10 100 50 50 60 40 9 9 45 27 54 36 x 8 7 9 2 16 14 18 3 24 21 27 4 32 28 36 8 64 56 72 1 8 7 9 6 48 42 54 7 56 49 63 5 40 35 45 10 80 70 90 1. 2. a) 54 3. (d) 7 x 10 = 70 4. (a) 10 x 10 = 100 (b) 63 (c) 72 (b) 7 x 8 = 56 9 72 63 81 (d) 81 (c) 9 x 8 = 72 (d) 8 x 8 = 64 34 Grade 4 (draft) Multiplication 5. x 8 3 6 7 9 1 8 3 6 7 9 2 16 6 12 14 18 4 32 12 24 28 36 8 64 24 48 56 72 3 24 9 18 21 36 6 48 18 36 42 72 7 56 21 42 49 63 6. (a) 8 x 9 = 72 (d) 6 x 8 = 48 (b) 7 x 8 = 56 (e) 8 x 8 = 64 (c) 6 x 9 = 54 7. (a) 4 x 6 = 24 (b) 3 x 7 = 21 (c) 3 x 9 = 27 5 40 15 30 35 45 10 80 30 60 70 90 9 90 27 54 63 81 (d) 5 x 8 = 40 DAY 6: MEMORANDUM 4. X1 (a) (b) (c) (d) (e) (f) (g) 4x1=4 6x1=6 7x1=7 2x1=2 5x1=5 9x1=9 10 x 1 = 10 X 10 4 x 10 = 40 6 x 10 = 60 7 x 10 = 70 2 x 10 = 20 5 x 10 = 50 9 x 10 = 90 10 x 10 = 100 X2 4x2=8 6 x 2 = 12 7 x 2 = 14 2x2=4 5 x 2 = 10 9 x 2 = 18 10 x 2 = 20 X 20 4 x 20 = 80 6 x 20 = 120 7 x 20 = 140 2 x 20 = 40 5 x 20 = 100 9 x 20 = 180 10 x 20 = 200 5. X3 X 30 X6 X 60 (a) 4 x 3 = 12 4 x 30 = 120 4 x 6 = 24 4 x 60 = 240 (b) 6x3= 6 x 30 = 6x6= 6 x 60 = (c) 7x3= 7 x 30 = 7x6= 7 x 60 = (d) 2x3= 2 x 30 = 2x6= 2 x 60 (e) 5x3= 5 x 30 = 5x6= 5 x 60 = (f) 9x3= 9 x 30 = 9x6= 9 x 60 = (g) 10 x 3 = 10 x 30 = 10 x 6 = 10 x 60 = x4 x 40 x8 x 80 4 x 4 = 16 4 x 40 = 160 4 x 8 = 32 4 x 80 = 320 3. (a) 35 Grade 4 (draft) Multiplication (b) 6 x 4 = 24 6 x 40 = 240 6 x 8 = 48 6 x 80 = 480 (c) 7 x 4 = 28 7 x 40 = 280 7 x 8 = 56 7 x 80 = 560 (d) 2x4=8 2 x 40 = 80 2 x 8 = 16 2 x 80 = 160 (e) 5 x 4 = 20 5 x 40 = 200 5 x 8 = 40 5 x 80 = 400 (f) 9 x 4 = 36 9 x 40 = 360 9 x 8 = 72 9 x 80 = 720 (g) 10 x 4 = 40 10 x 40 = 400 10 x 8 = 80 10 x 80 = 800 4. x5 x 50 x 70 x 90 (a) 4 x 5 = 20 4 x 50 = 200 4 x 70 = 28 4 x 90 = 360 (b) 6 x 5 = 30 6 x 50 = 300 6 x 70 = 420 6 x 80 = 480 (c) 7 x 5 = 35 7 x 50 = 350 7 x 70 = 490 7 x 80 = 560 (d) 2 x 5 = 10 2 x 50 = 100 2 x 70 = 140 2 x 80 =160 (e) 5 x 5 = 25 5 x 50 = 250 5 x 70 =140 5 x 80 = 400 (f) 9 x 5 = 45 9 x 50 = 450 9 x 70 = 630 9 x 80 = 720 (g) 10 x 5 = 50 10 x 50 = 500 10 x 70 = 700 10 x 80 = 800 5. (a) 50 x 20 = 100 (d)40 x 6 = 240 (g) 70 x 5 = 350 (j) 20 x 30 = 600 (b) 40 x 30 = 120 (e) 80 x 2 = 160 (h) 9 x 20 = 180 (k) 10 x 80 = 800 (c) 7 x 40 = 280 (f) 90 x 3 = 270 (i) 1 x 70 = 70 (l) 60 x 10 = 600 6. (a) 9 (b) 9 (c) 6 (d) 3 (e) 5 (f) 40 (g) 12 (h) 10 (i) 20 (j) (k) 9 (l) 7 7 7. 8. Total pancakes Cost in Rand 1 R7 2 R14 3 R21 4 R28 5 R35 6 R42 7 R49 8 R56 9 R63 Total pancakes Cost in Rand 10 R70 20 R140 30 R210 40 R280 50 R350 60 R420 70 R490 80 R560 90 R630 (a) 160 (b) 270 (c) 460 (d) 160 (e) 180 (f) 180 36 Grade 4 (draft) Multiplication DAY 7: MEMORANDUM 1. (a) (b) (c) (d) (e) (f) (g) (h) (i) (j) (k) (l) Multiplication number sentence 4 x 6 = 24 ___ x 8 = 32 27 = 3 x ___ ___ x 9 = 36 3 x ___ = 18 49 = ___ x 7 8 x ___ = 56 ___ x 8 = 64 63 = 7 x ___ ___ x 6 = 60 6 x ___ = 54 35 = ___ x 5 Division number sentence 24 ÷ 4 = 6 32 ÷ 8 = 4 27 ÷ 3 = 9 63 ÷ 9 = 7 18 ÷ 3 = 6 49 ÷ 7 = 7 56 ÷ 8 = 7 64 ÷ 8 = 8 63 ÷ 7 = 9 60 ÷ 6 = 10 54 ÷ 6 = 9 35 ÷ 5 = 7 2. (a) (b) (c) (d) (e) (f) (g) (h) Division number sentence 10 ÷ 2 = 5 9÷3= 12 ÷ 2 = 12 ÷ 3 = 12 ÷ 4 = 20 ÷ 4 = 10 ÷ 5 = 25 ÷ 5 = Multiplication number sentence 5 x 2 = 10 3x3=9 6 x 2 = 12 4 x 3 = 12 3 x 4 = 12 5 x 4 = 20 2 x 5 = 10 5 x 5 = 25 3. (a) Multiplication number sentence: ___ x 8 = 32 ; 4 x 8 = 32 Division number sentence : 32 ÷ 8 = ___; 32 ÷ 8 = 4 (b) Multiplication number sentence: 45 = 5 x ___ ; 45 = 5 x 9 Division number sentence : 45 ÷ 5 = ____ ; 45 ÷ 5 = 9 37 Grade 4 (draft) Multiplication 4. 5. (a) (b) (c) (d) (e) (f) Division number sentence 63 ÷ 7 = 9 35 ÷ 5 = 64 ÷ 8 56 ÷ 8 = 100 ÷ 10 = 90 ÷ 9 = Multiplication number sentence 7 x 9 = 63 5 x 7 = 35 8 x 8 =64 8 x 7 = 56 10 x 10 = 100 9 x 10 = 90 (g) (h) (i) (j) (k) (l) Division Number sentence 90 ÷ 10 = 81 ÷ 9 = 45 ÷ 5 = 28 ÷ 7 = 49 ÷ 7 = 72 ÷ 9 = Multiplication number sentence 10 x 9 = 90 9 x 9 = 81 5 x 9 = 45 7 x 4 = 28 7 x 7 = 49 9 x 8 = 72 6. 7. 6 x 4 x 5 = _______ 6x4x5 = 8. 35 ÷ 5 = 7 _______ 35 = 5 x 7 (Check) 24 x 5 = 120 DAY 8: MEMORANDUM 1. 38 Grade 4 (draft) Multiplication 2. 3. (a) 30 (b) 2 x 3 x 5 (c) learners count the bananas in diagram 4. (a) 30 (b) 3 x 5 x 2 (c) learners count the bananas in diagram 5. (a) 420 (b) 320 (c) 420 (d) 450 6. (a) 4 (b) 6 (c) 9 (d) 7 7. (a) Multiplication number sentence: ___ x 80 = 320 ; 4 x 80 = 320 Division number sentence: 320 ÷ 80 = ___ ; 320 ÷ 80 = 4 (b) Multiplication number sentence: ___ x 40 = 320 ; 8 x 40 = 320 Division number sentence : 320 ÷ 40 = ____ ; 320 ÷ 40 = 8 DAY 9: MEMORANDUM 1. (a) 1 634 (b)1 036 (c) 1 824 2. (a) R4 902 (b) R3 818 (c) R12 481 (d) R3 312 (e) R5 696 (f) R6 162 (d) 3 648 39 Grade 4 (draft) Multiplication 3. (a) R1 872 (c) 24 hours x 7days = 168 hours (b)1 980c = R19,80 (d) 60 minutes x 24 hours= 1 440 minutes DAY 10: MEMORANDUM 1. X: rows 2 (a) (b) (c) (d) (e) (f) (g) (h) (i) (j) (k) (l) 4 rows 3 stars 3 columns 4 stars 3 3; 6; 9; 12 4 4; 8;12 3 + 3 + 3 + 3 =12 4 + 4 + 4 =12 3 x 4=12 4 x 3=12 4 A B C 2 5 10 (a) (b) (c) (d) (e) (f) (g) (h) (i) (j) 2 rows; 5 circles 5 5; 10 5 + 5=10 2 x 5 =20 5 columns; 2 circles 2 2; 4; 6; 8; 10 2 + 2 + 2 + 2 + 2 =10 5 x 2=10 Y: columns 3 (a) (b) (c) (d) (e) (f) (g) (h) (i) (j) 5 rows/ rye; 4 triangles 4 4; 8; 12; 16; 20 4 + 4 + 4 + 4+ 4 =20 5 x 4 =20 4 columns; 5 triangles 5 5; 10; 15; 20 5 + 5+ 5 + 5 =20 4 x 5=20 40 Grade 4 (draft) Multiplication 5 (a) (b) (c) (d) (e) (f) (g) (h) (i) (j) 6 (a) (b) (c) (d) (e) 3 rows; 6 squares 6 (6): 6; 12; 18 6 + 6 + 6 = 18 3 X 6 = 18 6 columns; 3 squares 3 (3): 3; 6; 9; 12; 15; 18 3 + 3 + 3 + 3 + 3 + 3 =18 6 X 3 = 18 +5 8 (a) (b) (c) (d) (e) 7 (a) (b) (c) (d) (e) 3 rows; 5 circles (5): 5; 10; 15 5 + 5 + 5= 15 3 X 5 = 10 +5 5 rows;3 circles (3): 5; 10; 15 3 + 3 + 3 + 3 + 3 =15 5 X 3= 15 +5 +3 +3 +3 +3 +3 +3 5 bags; R7 (per bag) (7): 5; 10; 15 R7 + R7 + R7 + R7 + R7 = R35 5 X R7 = R35 +7 9. (a) 18 (b) 24 10. (a) 40 (b) 50 11. (a) 40 (b) 80 12. (a) 36 (b) 42 +7 +7 (c) 30 +7 +7 (d) 136 (e) 42 (f) 48 (g) 54 (d) 24 (e) 16 (f) 24 (g) 56 (h) 60 (c) 96 (c) 48 (h) 88 41 Grade 4 (draft) Multiplication 13. (a) 5x5+3x5 = 25 + 15 = 40 (b) (d) 9x5–4x5 = 45 - 20 = 25 (e) 12 x 5 = (10 +2) x 5 = (10 x 5) + ( 2 x 5) = 50 + 10 = 60 10 x 5 – 7 x 5 = 50 - 30 = 15 (c) 6x5+9x5 = 30 + 45 = 75 (f) 4x8 +5x5 = 32 + 25 = 57 14. (a) = = = = 27 x 8 (20 +7) x 8 (20 x 8) + ( 7 x 8) 160 + 56 216 (b) = = = = 43 x 5 (40 +3) x 5 (40 x 5) + (3 x 5) 200 + 15 215 (c) = = = = 6 x 59 6 x (50 +9) (6 x 50) + (6 x9) 300 + 54 354 (d) = = = = 2 x 88 2 x (80 +8) (2 x 80) + (2 x16) 160 + 16 176 15. (a) 8x6x5 (b) (c) 9x3x5 = 8x5x6 = 25 x 2 x 5 = 9x5x3 = 40 = 50 = 45 x6 = 240 (d) 25 x 5 x 2 x5 = 250 15 x 8 x 6 (e) x3 = 135 11 x 6 x 5 (f) 10 x 7 x 5 = 15 x 6 x 8 = 11 x 5 x 6 = 10 x 5 x 7 = 90 = 55 x 6 = 50 x 7 = 330 = 350 x8 = 720 16. (a) 24 (b) 18 (c) 12 17. (a) 6 (b) 18 (c) 4 (d) 12 18. (a) 12 (b) 24 (c) 9 (d) 18 19. (a) 56 ÷ 7 = 8 (b) 27 ÷ 9 = 3 (c) 33 ÷ 3 = 11 (d) 48 ÷ 8 = 6 (e) 25 ÷ 5 = 5 (f) 72 ÷ 8 = 9 (e) 6 (f) 12 42 Grade 4 (draft) Multiplication 20. (a) = = = = R39 x8 (30 +9) x 8 (30 x 8) + ( 9 x 8) R240 + R72 R312 (b) = = = = 55c x6 (50 +5) x 6 (50 x 6) + (5 x 6) 300c + 30c 330c or R3,30 (c) = = = = 24 x 7 (20 +4) x 7 (20 x 7) + (4 x 7) 140 + 28 hours 168 hours (d) = = = = 60 x 24 60 x (20 +4) (60x 20) + (60 4) 1 200 + 24 1 400 minutes 43 Grade 4 (draft) Multiplication