Multiplying and Dividing Fractions

Multiplying Fractions

When we multiply fractions, we multiply the numerators and then the denominators. Then you need to write the answer in lowest terms. You can also reduce the fractions and eliminate common factors before you multiply. This is a better method when you’re using large numbers. For example, when multiplying I can simplify the fractions before I multiply.

Multiplying Mixed Numbers

When you multiply mixed numbers, they need to be written as improper fractions. Then follow the process of multiplying and change it back to a mixed number if necessary.

mixednumbers

For example: multiplying mixed numbers.gif

Notice how I changed the mixed numbers to improper fractions. This will make multiplying the fractions easier! Now let’s discuss dividing fractions.

Division of Fractions

Reciprocals

Before we can talk about dividing, we need to define a reciprocal. The reciprocal of a fraction is found by switching the numerator and denominator.

recipricol

Dividing Fractions

When you divide fractions, you’ll take the reciprocal of the divisor and change the problem to a multiplication problem.

Here’s the general formula:

dividing

Dividing Mixed Numbers

When dividing mixed numbers, the same rules apply. Change the mixed numbers to improper fractions and then follow the rules for division.

 

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