5% as a fraction
Per cent means out of 100: 5% is 5/100, which simplifies to 1/20.
The answer
5% = 1/20
How to write 5% as a fraction
Per cent means out of 100, so write the percentage over 100: 5% = 5/100.
Simplify by dividing the top and bottom by the same number. In one go, divide by the highest common factor, 5: 5/100 = 1/20.
1 and 20 share no factor except 1, so 1/20 is the simplest form.
As a decimal, 5% = 0.05: divide by 100, which moves each digit two places to the right.
To check, divide back: see 1/20 as a decimal and 1/20 as a percentage.
Using 1/20 to find 5% of an amount
Knowing that 5% is 1/20 makes finding 5% of an amount quick: divide by 20.
5% of 40 = 40 ÷ 20 = 2
The bar model below opens on 5% of 40 and reaches the same answer another way, by working out 10% as 40 ÷ 10, then 5% as half of 10%. Change the numbers to try your own. Its bar is marked in tenths, so 5% stops partway through a tenth; the picture of 1/20 further down shows it exactly.
A bar model that finds a percentage of any amount, step by step. 5% of 40 is 2.
See 1/20
More percentages as fractions
Questions parents ask
What is 5% as a fraction?
5% = 5/100 = 1/20 in its simplest form.
What is 5% as a decimal?
5% = 0.05. Divide by 100: the digits move two places to the right.
How do you find 5% of an amount?
5% is 1/20, so divide by 20. For 5% of 40: 40 ÷ 20 = 2.
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