Math Background

Multiplying and Dividing Decimals: Tips and Tricks

  • On the chalkboard, have a student highlight the decimal places in the factors of a multiplication exercise, as in the example below. Have another student place the decimal point and highlight the decimal places in the product. Some students may need to be reminded to count digits to the right of decimal points when they count decimal places.
    multiplication problem
  • Show students that you can model decimal multiplication with graph paper and colored pencils. Use a 10 x 10 grid. To show 0.3 x 0.4, display the following model:
    multiplication problem and ten by ten grid
  • Many students have difficulty aligning digits, especially when finding the quotient in a division exercise. Have students complete some exercises by using graph paper, placing each digit in a square. This method will help them keep everything aligned appropriately.

Houghton Mifflin Math Grade 5