How to Divide a Decimal by a Whole Number

By Angie Papple Johnston

If you run into a question on the ASVAB Mathematics Knowledge subtest where you have to divide a decimal by a whole number, you can use the following technique to quickly find the right answer.

Here’s how to divide a decimal by a whole number:

  1. Move the decimal point over to the right until the decimal is a whole number, counting the number of decimal places.
    For example, if you want to find 125 ÷ 4, change 1.25 to 125 by moving the decimal two decimal places to the right. Remember how many places you moved the decimal—you need that info later.
  2. Perform the division operation on the whole number.
    125 ÷ 4 = 31.25
  3. In your answer, move the decimal point to the left the number of places you moved it in Step 1.
    To make up for moving the decimal point two places to the right when you made 1.25 into a whole number, move the decimal point two places to the left in 31.25. Your answer is 0.3125.