Rounding decimal numbers

To round a decimal number to one order of units:

- We remove all the digits at the right of this order of units.

- If the first removed digit is greater than or equal to 5, we add 1 to the digit on the left.

Examples:
· If we round 3.53 to the nearest tenth we obtain 3.5
· If we round 2.88954 to the nearest hundredth we obtain 2.89

Exercise: round

a) 3.13 to the nearest tenth

b) 3.8957 to the nearest hundredth

c) 21.5 to the nearest unit

Solutions: a) 3.1; b) 3.90; c) 22