Question

How to do estimation by rounding numbers? ​

Answer 1

Step-by-step explanation:  If we’ve rounded one amount up and one down, the sum we have obtained is a correct estimation. If both summands have been rounded up and the amount of rounding is greater than 5, we subtract 10 from the estimate. If both summands have been rounded down and the amount of rounding is greater than 5, we add 10 to the estimate.

Answer 2

Answer:

The general rule for estimating is to look at the digit to the right of the digit you want to estimate. Estimating or rounding to the nearest whole number means looking at the digit to the right of the decimal. If you see a digit greater than 5, round up, and if it's less than 5, round down.