1. Whiteboardmaths.com
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2. Percentages of Quantities
Remember: A percentage is simply a fraction out of 100.
23%
56%
84% 23
100 56
100 84
100

3. Percentages of Quantities
Remember: A percentage is simply a fraction out of 100.
Calculating percentages using a calculator
23%
Example 1: Calculate 23% of $56
$56 23
100
of 56 23
100
x 56 2 3 1 x 5 6 = 23
100
$12.88
Calculator

4. Percentages of Quantities
Remember: A percentage is simply a fraction out of 100.
Calculating percentages using a calculator
58%
Example 2: Calculate 58% of 34 kg 58
100
of 34 58
100
x 34
34 kg 58
100 5 8 1 x 3 4 =
19.72 kg

5. Percentages of Quantities
Remember: A percentage is simply a fraction out of 100.
Calculating percentages using a calculator
87%
Example 3: Calculate 87% of 45 m
45 m 87
100
of 45 87
100
x 45 87
100 8 7 1 x 4 5 =
39.15 m

6. Percentages of Quantities
Use your calculator to calculate the following.
Q 1: Calculate 54% of $89
Q 2: Calculate 17% of 33 m
$48.06
5.61 m
Q 3: Calculate 84% of 350 g
Q 4: Calculate 24% of $450
294 g
$108
Q 5: Calculate 71% of 28 l
Q 6: Calculate 43% of 16 kg
19.88 l
6.88 kg
Q 7: Calculate 7% of $750
Q 8: Calculate 39% of 7.2 km
$52.50
2.808 km

7. Percentages of Quantities
Remember: A percentage is simply a fraction out of 100.
A more efficient method using a decimal
36%
Example 4: Calculate 36% of $84 36
100
of 84 36
100
x 84
$84 . 3 6 x 8 4 = 36
100
= 0.36
$30.24

8. Percentages of Quantities
Remember: A percentage is simply a fraction out of 100.
A more efficient method using a decimal
93%
Example 5: Calculate 93% of 73 kg
73 kg 93
100
of 73 93
100
x 73 93
100 . 9 3 x 7 3 =
= 0.93
67.89 kg

9. Percentages of Quantities
Remember: A percentage is simply a fraction out of 100.
Calculating percentages using a calculator 8%
Example 6: Calculate 8% of 67 m
67 m 8
100
of 67 8
100
x 67 8
100 . 8 x 6 7 =
= 0.08
5.36 m

10. Percentages of Quantities
Use your calculator with a decimal to calculate the following:
Q 1: Calculate 54% of $43
Q 2: Calculate 17% of 85 m
$23.22
14.45 m
Q 3: Calculate 84% of 830 g
Q 4: Calculate 24% of $674
697.2 g
$161.76
Q 5: Calculate 3% of 28 l
Q 6: Calculate 9% of 16 kg
0.84 l
1.44 kg
Q 7: Calculate 99% of $750
Q 8: Calculate 63% of 7.2 km
$742.5
4.536 km

11. Percentages of Quantities
Remember: A percentage is simply a fraction out of 100.
Calculating general percentages without a calculator
23%
Example 1: Calculate 23% of $56
Simply complete the multiplication sum with the given numbers then position the decimal point.
$56
5 6
x 2 3
5 6
x 2 3 8 2
1 6
1 1
or if you prefer
1 6 8 23
100
1 1 2
= 0.23
$12.88
Non Calc
Position 2 places from right

12. Percentages of Quantities
Remember: A percentage is simply a fraction out of 100.
Calculating general percentages without a calculator
47%
Example 2: Calculate 47% of 65 m
Simply complete the multiplication sum with the given numbers then position the decimal point.
65 m
6 5
x 4 7
6 5
x 4 7
2 6 5
4 5
or if you prefer
4 5 5 47
100
2 6
= 0.47
30.05 m
Position 2 places from right

13. Percentages of Quantities
Remember: A percentage is simply a fraction out of 100.
Calculating general percentages without a calculator 9%
Example 3: Calculate 9% of 546 kg
Simply complete the multiplication sum with the given numbers then position the decimal point.
546 kg
5 4 6
x 9
4 9 1 4 9
100
Position 2 places from right
= 0.09
49.14 kg

14. Percentages of Quantities
Calculate the following without a calculator.
Q 1: Calculate 52% of $79
Q 2: Calculate 27% of 43 m
$41.08
11.61 m
Q 3: Calculate 74% of 270 g
Q 4: Calculate 18% of $490
199.8 g
$88.2
Q 5: Calculate 85% of 28 l
Q 6: Calculate 7% of 16 kg
23.8 l
1.12 kg
Q 7: Calculate 4% of £750
Q 8: Calculate 99% of 7.2 km
£30
7.128 km

15. Percentages of Quantities
Use your calculator to calculate the following.
Q 1: Calculate 54% of $89
Q 2: Calculate 17% of 33 m
Q 3: Calculate 84% of 350 g
Q 4: Calculate 24% of $450
Q 5: Calculate 71% of 28 l
Q 6: Calculate 43% of 16 kg
Worksheet1
Q 7: Calculate 7% of $750
Q 8: Calculate 39% of 7.2 km

16. Percentages of Quantities
Use your calculator with a decimal to calculate the following:
Q 1: Calculate 54% of $43
Q 2: Calculate 17% of 85 m
Q 3: Calculate 84% of 830 g
Q 4: Calculate 24% of $674
Q 5: Calculate 3% of 28 l
Q 6: Calculate 9% of 16 kg
Worksheet 2
Q 7: Calculate 99% of $750
Q 8: Calculate 63% of 7.2 km

17. Percentages of Quantities
Calculate the following without a calculator.
Q 1: Calculate 52% of $79
Q 2: Calculate 27% of 43 m
Q 3: Calculate 74% of 270 g
Q 4: Calculate 18% of $490
Q 5: Calculate 85% of 28 l
Q 6: Calculate 7% of 16 kg
Worksheet3
Q 7: Calculate 4% of $750
Q 8: Calculate 99% of 7.2 km