Rounding decimals
Zoom in between a number's two neighbours and see which is nearer: to the nearest whole number, to 1 and 2 decimal places, and to significant figures. Then find every number that rounds to the same value.
- UK: Year 4
- France: grade 4
- Germany: grade 6
- Iran: grade 6
- Ukraine: grade 5
- Russia: grade 5
Guide
To round a number, find its two neighbours and see which one it is nearer to. For example, 3.7 is between 3 and 4 and is nearer 4, so 3.7 rounds to 4 (to the nearest whole number).
If a number is exactly halfway, like 3.5, we round up.
Rounding is not the same as cutting off (truncating). Cutting off just drops the digits: 3.7 becomes 3. Rounding picks the nearest: 3.7 becomes 4.
"To 1 decimal place" (1 d.p.) means to the nearest tenth; "to 2 decimal places" means to the nearest hundredth.
The small line at the top shows the whole number line; the coloured piece is the part shown magnified underneath.