year 8 maths

4F
Converting fractions, decimals and percentages
231
Example 18
Converting percentages to fractions
Convert the following percentages to fractions or mixed numerals in their simplest form.
a 160%
b 12.5%
SOLUTION
a 160% = 160
100
= 8 × 20
5 × 20
= 8 5 = 1 3 5
EXPLANATION
Change % sign to a denominator of 100 .
Cancel the HCF.
Convert answer to a mixed numeral.
b 12.5% = 12.5
100
= 25
200
= 1 8
or = 12.5
100
= 125
1000
= 1 8
Change % sign to a denominator of 100 .
Multiply numerator and denominator by 2 or by 10 to
make whole numbers.
Simplify fraction by cancelling the HCF.
Example 19
Converting percentages to decimals
Convert the following percentages to decimals.
a 723%
b 13.45%
SOLUTION
EXPLANATION
a 723% = 7.23 723 ÷ 100 723.
Decimal point appears to move two places to the left.
b 13.45% = 0.1345 13.45 ÷ 100 13.45
Cambridge Maths NSW
Stage 4 Year 8 Second edition
ISBN 978-1-108-46627-1 © Palmer et al. 2018
Cambridge University Press
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