0.45 as a fraction
0.45 is 45 hundredths, so write it as 45/100 and simplify to 9/20.
The answer
0.45 = 9/20
How to write 0.45 as a fraction
Put the digits in a place value chart. The place of the last digit tells you the bottom of the fraction.
| Ones | Tenths | Hundredths |
|---|---|---|
| 0 | 4 | 5 |
The last digit is in the hundredths column, so 0.45 is 45 hundredths: 45/100.
Simplify by dividing the top and bottom by the same number. In one go, divide by the highest common factor (the biggest whole number that divides both exactly), 5: 45/100 = 9/20.
9 and 20 share no factor except 1, so 9/20 is the simplest form.
As a percentage, 0.45 = 45%: multiply by 100, which moves each digit two places to the left.
To check, divide back: see 9/20 as a decimal and 9/20 as a percentage.
See 9/20
More decimals as fractions
Questions parents ask
What is 0.45 as a fraction in its simplest form?
0.45 = 45/100 = 9/20. Divide the top and bottom of 45/100 by 5 to get 9/20.
How do you write 0.45 as a fraction?
The last digit of 0.45 is in the hundredths column, so write the digits over 100: 45/100. Then simplify if you can.
What is 0.45 as a percentage?
0.45 = 45%. Multiply by 100: the digits move two places to the left.
Continue your maths practice
Explore the diagnostic for another way to practise.