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Fractions, decimals and percentages
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Fractions, decimals and percentages are three ways of writing the same amount. Percent means number of parts per hundred.
Converting
Percentage to decimal: divide by 100. 35% = 0.35
Decimal to percentage: multiply by 100. 0.6 = 60%
Fraction to decimal: divide the top by the bottom. 38 = 3 ÷ 8 = 0.375
Terminating decimals can be written as fractions: 3.5 = 72.
Decimal to percentage: multiply by 100. 0.6 = 60%
Fraction to decimal: divide the top by the bottom. 38 = 3 ÷ 8 = 0.375
Terminating decimals can be written as fractions: 3.5 = 72.
Fractions of amounts
A fraction can act as an operator. Divide by the bottom, multiply by the top.
34 of 48: 48 ÷ 4 = 12, 12 × 3 = 36.
34 of 48: 48 ÷ 4 = 12, 12 × 3 = 36.
Percentages of amounts
Build from 10%: divide by 10.
20% of 65: 10% = 6.5, so 20% = 13.
Or use a decimal: 20% of 65 = 0.2 × 65 = 13.
20% of 65: 10% = 6.5, so 20% = 13.
Or use a decimal: 20% of 65 = 0.2 × 65 = 13.
Write 45% as a fraction in its simplest form.
- 45% = 45100
- Divide top and bottom by 5
Answer: 920
To change a percentage to a decimal, divide by 100. For a fraction of an amount, divide by the bottom and multiply by the top.
The interactive lesson includes the diagrams for this topic.
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