0.8 as a fraction
0.8 is 8 tenths, so write it as 8/10 and simplify to 4/5.
The answer
0.8 = 4/5
How to write 0.8 as a fraction
Put the digits in a place value chart. The last digit tells you the bottom of the fraction.
| Ones | Tenths |
|---|---|
| 0 | 8 |
The last digit is in the tenths column, so 0.8 is 8 tenths: 8/10.
Simplify by dividing the top and bottom by the same number. In one go, divide by the highest common factor, 2: 8/10 = 4/5.
4 and 5 share no factor except 1, so 4/5 is the simplest form.
As a percentage, 0.8 = 80%: multiply by 100, which moves each digit two places to the left.
To check, divide back: see 4/5 as a decimal and 4/5 as a percentage.
See 4/5
Shade 4/5 on a fraction wall
The wall opens with 4/5 shaded in the fifths row. Look straight down: the shading ends in exactly the same place in 8/10, so it is equal to 4/5. Tap other pieces to try more fractions.
A fraction wall from halves to tenths, opening on 4/5.
More decimals as fractions
Questions parents ask
What is 0.8 as a fraction in its simplest form?
0.8 = 8/10 = 4/5. Divide the top and bottom of 8/10 by 2 to get 4/5.
How do you write 0.8 as a fraction?
The last digit of 0.8 is in the tenths column, so write the digits over 10: 8/10. Then simplify if you can.
What is 0.8 as a percentage?
0.8 = 80%. Multiply by 100: the digits move two places to the left.
Fractions, decimals and percentages run all through 11+ maths
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