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• • • • • • • Explanation This is a number line method. First you write the sum you are doing. Next you draw a neat ruler line. Then at the start of the number line you write the biggest number in your sum. You partition the smallest number in your sum so it is easier to add. Finally you do jumps of which ever number you feel comfortable with. options Skills you need to know for this method. Red=70+15 using number line You need to be good at addition. You need to choose numbers you feel comfortable with. Amber=66+43 using number line Green=227+336 using number line Choose an activity. +10 +10 +10 +2 86 54 54+32=86 This is your addition sum. Your smallest number is 32 so you partition 30 in to 3 tens and 2 in to 2 units. Click to go back to menu Open vertical method • • • • • • First write your calculation. Next write H.T.U. Then you complete you addition. First add the Units, then the Tens, then the Hundreds. You will do H.T.U as long as you go down. Finally add all of the digits in each column to find your total. Rag activates. R 85 + 325 = A 600 + 360 = G 7000 + 2423 = 1. 150 +235 =385 H T U 15 0 2 3 5 0 0 5 U 0 80 T 3 0 0H 3 8 5 2. 185 + 300 = 485 H T U 1 8 5 30 0 0 05 U 0 8 0 T 4 0 0 H 4 8 5 Why don’t you try one of these. Click to go back to menu • Write a addition sum. • Partition the smallest number that you have into hundreds, tens and units etc. For example 88+31=? Partition the number 31 to 30 and 1. • Then you do 88+30=118 because we partition the number 31 to 30 and 1. • Then you add 1 to your answer which was 118. • 118+1=119 because I got the 1from the 31. • That's how we get the answer. Step by step partitioning Red:60+35=? Amber:130+390=? Green:254+3105=? Example 450+163=613 100 60 3 450+100=550 550+60=610 610+3=613 Click to go back to menu Compensation. Addition. 54+49= Compensation helps you get the answer quickly by adding easier numbers together. Red – 28+19= • Step 1 write your sum which is 54+49. • Step 2 round the smallest number to 50. 49 50. • Step 3 do 54+50=104 • Step 4 take away 1 unit from the answer that you got which was 104-1=103 Your answer should be 103. Amber - 42+39= Green – 133+59= Click to go back to menu Subtraction number line Red13-8= Amber48-19= •First you draw a line. •Then you put the smallest number at the beginning of the line and the biggest number at the end. •Next you have to use the opposite operation which is addition. If you add 4 to 16 you will get 20 which is a multiple of 10.Multiples of 10 are very easy to work with. Green 81-36= 29-16=13 +4 16 +9 20 29 •Then you add 9 to 20 because we want to get to 29 and when you add 9 to 20 that will equal 29. •Finally you add the jumps which are 9 and 4 this equals 13 and that is the answer. Click to go back to menu Subtraction. Difference. 78-56= • First start with the smallest number. Work out how many units needs to be added to this number to get it to the nearest multiple of 10 when counting upwards. 56 • After that you add 8 units because the number that we are trying to get to is 78 so we are at 70 and we need to add 8 more units to get to 78. 60 = 4. Next write the number you added (4) on to 56 to get to 60 in the correct column on a place value chart. HTU 60 + 0 0 4 56 • • Then you work out how many tens you need to add to get to the multiple of 10 closest to the larger number. 56 60 Click to go back to menu HTU 60 + 0 0 4 70 + 0 1 0 56 60 70 • HTU 60 + 0 0 4 70 + 0 1 0 78 + 0 0 8 Finally you add the H T U together because then you will get your answer. HTU 56 60 + 0 0 4 60 70 + 0 1 0 70 78 + 0 0 8 012U 010T 022 Your answer should be 22. Subtraction. Partitioning. Example: 68-43=25 40 3 68-40=28 28-3=25 R 53-32=? A 68-106=? G 346-378=? 1. First you partition the smallest number into units, tens, hundreds (etc.) 2. Then with the biggest number you take away the tens from it. 3. Finally with the answer you’ve got, take away the units from it. The answer you should have is 25. Click to go back to menu Subtraction Counting on. Counting on is an efficient strategy when subtracting 2 numbers that are close together. Red=32-28= For example: 1002-997= Amber=173-167= Green=3562-3554= In this example you have to round up the smallest number which is 997 to 1000 (Add 3). After that you have to count on from 1000 to 1002 (Add 2). Finally you add 3 and 2 together which gives you your answer 5. Click to go back to menu. Practice question 5x4= 3x5=… … … … … 3x6=… … … … … … 3x7=… … … … … … … Times tables facts Your times tables facts will really help you know your times tables. If you know how to double you can use your 3 times tables to find your 6 times tables and you can use your 2 times tables to find your 4 times tables. Knowing your times tables facts let you answer multiplication problems easily. You can use your time tables facts to solve really hard problems. RAG activities Red 1. 10x5= 2. 5x5= 3. 4x2= Click to go to menu Green 1. 8x9= 2. 9x7= 3. 8x6= The order to learn your times tables in. 1. 1x 2. 2x 3. 5x 4. 10x 5. 3x 6. 4x 7. 6x 8. 8x 9. 9x 10. 7x 1x0= 1x1= 1x2= 1x3= 1x4= 1x5= 1x6= 1x7= 1x8= 1x9= 1x10= 2x0= 2x1= 2x2= 2x3= 2x4= 2x5= 2x6= 2x7= 2x8= 2x9= 2x10= 3x0= 3x1= 3x2= 3x3= 4x3= 5x3= 6x3= 7x3= 8x3= 9x3= 10x3 Red is if you want an easy sum. Amber is if you want to challenge your self. 1. First you partition the number that you do Green is if you not know times tables facts for. really want to 2. Next you complete the separate push your calculations. self. 3. Then add up the separate totals and you will get your answer. Example: 9X6=54 Have a go… 7x8=? 5 4 5x6=30 4x6=24 30+24=54 ? ? ?x?= ?x?= ?+?= Reded. Amber. Green. R,6x4= A,7x8= G,18x7= Click to go to menu Compensation This helps you with your 9 x table Step By Step Write your calculation. E.G 6x9= First change the 9 into a 10 because it’s easier to multiply by 10. Then do 6 x 10 = 60 because you changed 9 to 10. After that do 60 – 6 = 54 because you added an extra 6. And there’s your answer. 135 x 9= 135 x 10 = 81 x 9 = 81 x 10 = Example : 79 x 9 = 711 79 x 10 = 790 790 – 79 =711 63 x 9 = 63 x 10 = Click to go to menu • Step by step • • • • • • • • • • • • • • • • 1] First draw a Grid. 2] Then draw an X in the left hand Corner. 3] Next partition 29 into 20 and 9 and 19 into 10 and 9. 4]Then place them Into the grid on the top and the left hand side. 5]Then times 10 by 20 which equals 200.Then do 9x10=90 then 20x9=180 then 9x9=81. Finally add 200,90,180 and 81 Grid method 1. Draw the grid. 29x19= 551 x 10 9 200+180=380 90+81=171 171+380=551 20 9 200 180 90 2. Draw an x in the x left hand corner. x x 10 9 3. Partition 29 into 20 and 9 81 Click to go to menu Step by step instructions: (Ignore the 6 above 36 for now). 1) If your sum was 36 divided by 6 then this would be how you lay it out: • The number that you are dividing by goes on the left hand side of the box. 6 • Then you will put the number that you are dividing here. 6 36 2)We will have to use our multiplication knowledge to find out how many groups of 6 are in 36. 3)To make it easier we will do 6x3 because if you know your multiplication facts the answer is 18 which is less than 36.(While using the chunking method, you cannot go over the number you are dividing). Click to go back to menu Chunking method 6 6 36 18 6x3 18 18 6x3 0 A remainder is a number that is leftover. RAG: R-48 divided by 4 A-67 divided by 8 G-74 divided by 6 4)Now we shall find the difference between 36 and 18 which is 18. • But we still haven’t got our answer yet, so we will do 6x3 again. 5)Now we have to find the difference between 18 and 18 which is 0. 6)Now we need to add up the numbers that we have multiplied 6 by,(3 and 3) which equals 6. Our answer is 6 so write it at the top! Tip. If there is a remainder write it like this: r 3 or whatever the remainder is at the bottom, (where the 0 is). Division on a number line 32 divided by 5 =6r2 First we started with 0 and added 1 group of 5.Then we added 6 groups of 5 until we got to 30.We couldn’t add another group of 5 .Our number was 32,so we had 2 left over. The answer was 6 remainder 2. +5 +5 5 0 6 6 12 +5 +5 20 15 10 6 6 0 +5 6 18 r2 +5 25 30 r2 24 divided by 6 = 4 24 First we started with 0 and added one group of 6.Then we added another group of 6. After that we added 2 more groups of 6.Then we got our answer 4 because we added 4 groups of six to get 24. Click to go back to menu Division facts • If you are not comfortable with your times tables you need to go to the times tables slide because all of these division methods need you to have some understanding of your times tables. • If you don’t want remainders or decimals here are some rules you can follow: • • • • • You can only divide numbers by 3 that are in the 3 times table. You can only divide numbers by 4 that are in the 4 times table. You can only divide numbers by 5 that are in the 5 times table. You can only divide numbers by 6 that are in the 6 times table. The same rule applies for all numbers. Click to go back to menu