15% as a fraction
Per cent means out of 100: 15% is 15/100, which simplifies to 3/20.
The answer
15% = 3/20
How to write 15% as a fraction
Per cent means out of 100, so write the percentage over 100: 15% = 15/100.
Simplify by dividing the top and bottom by the same number. In one go, divide by the highest common factor, 5: 15/100 = 3/20.
3 and 20 share no factor except 1, so 3/20 is the simplest form.
As a decimal, 15% = 0.15: divide by 100, which moves each digit two places to the right.
To check, divide back: see 3/20 as a decimal and 3/20 as a percentage.
Using 3/20 to find 15% of an amount
Knowing that 15% is 3/20 makes finding 15% of an amount quick: divide by 20 to find 1/20, then multiply by 3.
15% of 40 = 40 ÷ 20 × 3 = 2 × 3 = 6
The bar model below opens on 15% of 40 and reaches the same answer another way, by building 15% from 10% and 5%. Change the numbers to try your own. Its bar is marked in tenths, so 15% stops partway through a tenth; the picture of 3/20 further down shows it exactly.
A bar model that finds a percentage of any amount, step by step. 15% of 40 is 6.
See 3/20
More percentages as fractions
Questions parents ask
What is 15% as a fraction?
15% = 15/100 = 3/20 in its simplest form.
What is 15% as a decimal?
15% = 0.15. Divide by 100: the digits move two places to the right.
How do you find 15% of an amount?
15% is 3/20, so divide by 20, then multiply by 3. For 15% of 40: 40 ÷ 20 = 2, and 2 × 3 = 6.
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