Simplifying Fractions before Multiplying

Big Idea:

By simplifying fractions before we multiply, we make the multiplication easer and leave the answer in its simplest form. Some people refer to this as pre-reducing, cross-reducing, or canceling. Whatever you call it, it’s a shortcut.

Simplifying Fractions before Multiplying


You can save work in some multiplication problem by simplifying before you multiply.

Step 1. Find one numerator and one denominator with a common factor. 2 and 4 have a common factor
Step 2. Divide these numbers by their common factor. simplify the fraction
Step 3. Repeat the process if there are other numerators and denominators with a common factor. 3 and 9 have common factors
Step 4. You can also reduce variables. simplify 3 and 9
Step 5. Multiply across. pre-reducing the fraction


This might be fun to look at next:

One Step Equations: Multiplication Problems with Fractions