Question

When dividing 918 by 4.2, what number should the divisor be multiplied by in order to make it a whole number

Answer 1

10, Because the divisor, 4.2, has only value in the ones and tenths places, so we only have to multiply by 10 to get to 42, which is the whole number you need.

Explanation:

Answer 2

To make 4.2 a whole number, we need to make the decimal places equal to zeros

4.2 = 4 + 0.2

Think of a number that multiplied by 0.2 gives a whole number. The smallest number possible will be 5 since 0.2 × 5 = 1

So we multiply 4.2 by 5

4.2 × 5 = [4 × 5] + [0.2 × 5] = 20 + 1 = 21

Applying this change into the whole sum

918 ÷ 4.2
[918 ÷ 4.2] × 5 = [918 × 5] ÷ [4.2 × 5] = 4590 ÷ 21

Now you have a sum whose terms in whole numbers only