Answer :
*Compatible numbers are pairs of numbers that are easy to add, subtract, multiply, or divide mentally. When using estimation to approximate a calculation, replace actual numbers with compatible numbers.
*Rounding numbers means adjusting the digits to make rough calculations easier. The result will be an estimated answer rather than a precise one.
According to the previous definitions, we can conclude:
_Both ways give an approximate solution.
_One way may give an estimate that is closer to the actual solution than the other method