Mass is measured in grams or kilograms. 1 000 g = 1 - E

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GRADE 5
Name:
Mass is measured in grams or kilograms.
Remember:
1 000 g = 1 kg
• If a fraction has
been given with the
kilograms, it means
that the fraction is
a part of a kilogram
(1 kg = 1 000g).
250 g =
500 g =
1
4 kg = 0,25 kg
1
kg = 0,5 kg
2
Example: Converting – grams to kilograms
5 000 g ÷ 1 000 = 5 kg
3 400 g = (3 000 ÷ 1 000) + 400 g = 3 kg 400 g
Example: Converting kilograms to grams
5 kg × 1 000 = 5 000 g
2,5 kg = (2 kg × 1 000) + 500 g = 2 000 + 500 = 2 500 g
3
34 kg = (3 × 1 000) + (1 000 ÷ 4 × 3) = 3 000 + 750 = 3 750 g
• You will have to
divide 1 000g with the
denominator of the
fraction and multiply
this answer with the
numerator of the
fraction.
Questions:
1. Write down (in the table) the most suitable unit of mass that you would use to
measure the following objects with:
Object
a)
Paperclip
b)
Television
c)
Tennis ball
d)
Your own mass
e)
School bag without books
f)
School bag with books
Unit of mass
2. Read the masses from each scale and write them down in both grams and kilograms.
a)_______________________ b)
_______________________
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Grade 5 Term 3 Mathematice: Measurement; Mass
Mass
GRADE 5
c)_______________________
3. Convert the following masses from kilograms to grams: (Show all your working out.)
a) 5 14 kg = ____________________________________________________
b) 8 kg = ______________________________________________________
c) 3,5 kg = _________________________________________________________
d) 60 kg =
______________________________________________________
4. Convert the following masses from grams to kilograms: (Show all you working out.)
a) 7 800 g = ________________________________________________________
b) 9 250 g = ________________________________________________________
c) 500 g =
d) 19 000 g = _______________________________________________________
______________________________________________________
5. Arrange the following masses in ascending order:
25 kg 600 g; 25,5 kg; 19 000 g; 23 250 g; 30 kg
___________________________________________________________________
6. Arrange the following masses in descending order:
25 kg 600 g; 25,5 kg; 19 000 g; 23 250 g; 30 kg
________________________________________________________________
7. What do you notice in question 5 and 6 above?
___________________________________________________________________
___________________________________________________________________
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Grade 5 Term 3 Mathematice: Measurement; Mass
Mass
GRADE 5
8. Round these mass measurements off to the nearest 100 kg.
a) 123 kg ≈ ______________
b)
572 kg ≈ _______________
9. Calculate and write each answer in grams and kilograms: (Show all your working out.)
a) 19,5 kg + 26 kg – 7 kg 500 g =________________________________________
b) 125g × 12 = ______________________________________________________
c) 35 of 2,5 kg = ______________________________________________________
d) 288 kg ÷ 12 = _____________________________________________________
e) What is the difference between 3 kg 16 g and 7 kg 70 g?
________________________________________________________________
f ) How much mass is needed to make up 15 kg from 7 kg 315 g?
________________________________________________________________
________________________________________________________________
10. Solve these problems: (Show all your working out.)
a)
Tammy wants to bake 12 muffins. She has a recipe for 6 muffins. The
recipe explains that she will have to use 500 g of flour for every 2 eggs
she uses. How much flour would Tammy need to bake 12 muffins?
___________________________________________________________
___________________________________________________________
___________________________________________________________
___________________________________________________________
b)
1
John went to the mall and bought 32 kg of sweets for R12/kg. He also
1
bought 1 4 kg of biltong for R76/kg and 300 g of chocolate for R10 for
each 100 g. How much money did John spend in the mall?
___________________________________________________________
___________________________________________________________
___________________________________________________________
___________________________________________________________
© e-classroom 2014
www.e-classroom.co.za
Grade 5 Term 3 Mathematice: Measurement; Mass
Mass
GRADE 5
1. Write down (in the table) the most suitable unit of mass that you would use to measure the following objects with:
a)
b)
c)
d)
e)
f)
Object
Paperclip
Television
Tennis ball
Your own mass
School bag without
books
School bag with
books
Unit of mass
Grams
Kilograms
Grams
Kilograms
Grams
Kilograms
2. Read the masses from each scale and write them down in both grams and kilo
grams.
a) 67 kg or 67 000 g
c) 175 g
b)
123,5 kg or 123 500 g
3. Convert the following masses from kilograms to grams: (Show all your working out.)
a) 5 14 kg = (5 × 1 000) + (1 000 ÷ 4 × 1) = 5 000 + 250 = 5 250 g
b)8 kg = 8 × 1 000 = 8 000 g
c) 3,5 kg = (3 × 1 000) + 500 g = 3 000 + 500 = 3 500 g
d)60 kg =
60 × 1 000 = 60 000 g
4. Convert the following masses from grams to kilograms: (Show all you working out.)
a) 7 800 g = (7 000 ÷ 1 000) + 800 = 7 kg 800 g
b)9 250 g = (9 000 ÷ 1 000) + 250 = 9kg 250 g = 9,25 kg
c) 500 g = 0 kg 500 g = 0,5 kg = 2 kg
d)19 000 g = 19 000 ÷ 1 000 = 19 kg
1
5. Arrange the following masses in ascending order:
25 kg 600 g; 25,5 kg; 19 000 g; 23 250 g; 30 kg
© e-classroom 2014
www.e-classroom.co.za
Grade 5 Term 3 Mathematice: Measurement; Mass
Answer sheet
GRADE 5
Grade 5 Term 3 Mathematice: Measurement; Mass
Answer sheet
Convert: 25 600 g; 25 500 g; 19 000 g; 23 250 g; 30 000 g
Answer: 19 000 g; 23 250 g; 25,5 kg; 25 kg 600 g; 30 kg
6. Arrange the following masses in descending order:
25 kg 600 g; 25,5 kg; 19 000 g; 23 250 g; 30 kg
Convert: 25 600 g; 25 500 g; 19 000 g; 23 250 g; 30 000 g
Answer: 30 kg; 25 kg 600 g; 25,5 kg; 23 250 g; 19 000 g
7. What do you notice in question 5 and 6 above?
Ascending order – masses ordered from smallest to highest in value.
Descending order – masses ordered from biggest to smallest in value.
8. Round these mass measurements off to the nearest 100 kg.
a) 123 kg ≈ 100 kg
b)
572 kg ≈ 600 kg
9. Calculate and write each answer in grams and kilograms: (Show all your working out.)
a) 19,5 kg + 26 kg – 7 kg 500 g = 38 kg = 38 000 g
b)125 g × 12 = 1 500 g = 1,5 kg or 1 kg
c)
d)288 kg ÷ 12 = 24 kg = 24 000 g
e) What is the difference between 3 kg 16 g and 7 kg 70 g?
3
5
of 2,5 kg = 2 500 g ÷ 5 × 2 = 1 000 g = 1 kg
7 070 g – 3 016 g = 4 054 g = 4 kg 54 g
f ) How much mass is needed to make up 15 kg from 7 kg 315 g?
15 000 g – 7 315 g = 7 685 g = 7 kg 685 g
© e-classroom 2014
www.e-classroom.co.za
GRADE 5
10. Solve these problems: (Show all your working out.)
a) Tammy wants to bake 12 muffins. She has a recipe for 6 muffins. The recipe explains that she will have to use 500 g of flour for every 2 eggs she uses. How much flour would Tammy need to bake 12 muffins?
6 muffins × 2 = 12 muffins
500 g × 2 = 1 000 g or 1 kg
Tammy will need 1 kilogram of flour to bake 12 muffins.
1
1
b) John went to the mall and bought 3 2 kg of sweets for R12/kg. He also bought 14 kg of biltong for R76/kg and 300g of chocolate for R10 for each 100g. How much money did John spend in the mall?
Sweets: (R12 × 3) + (R12 ÷ 2 × 1) = R36 + R6 = R42
Biltong: (R76 × 1) + (R76 ÷ 4 × 1) = R76 + R19 = R95
Chocolate: 300 g ÷ 100 g = 3
R42 + R95 + R30 = R167
John spent R167 at the mall.
3 × R10 = R30
© e-classroom 2014
www.e-classroom.co.za
Grade 5 Term 3 Mathematice: Measurement; Mass
Answer sheet
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