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Multiplying and Dividing Fractions — Reciprocals Made Easy

Editorial
7 min read
2026-02-25
Multiplying and Dividing Fractions — Reciprocals Made Easy

Multiplying and Dividing Fractions — Reciprocals Made Easy

Multiplying and dividing fractions follow simple rules — simpler than addition and subtraction since no common denominator is needed!

Multiplying Fractions

**Rule:** Numerator times numerator, denominator times denominator.

**Example:** 2/3 × 4/5 = (2 × 4) / (3 × 5) = 8/15.

**Tip:** You can cross-cancel before multiplying: with 3/4 × 2/9, cancel the 3 and 9 (by 3) and the 2 and 4 (by 2): 1/2 × 1/3 = 1/6.

Multiplying a Fraction by a Whole Number

Write the whole number as a fraction with denominator 1: 3/4 × 5 = 3/4 × 5/1 = 15/4 = 3 3/4.

What Is the Reciprocal?

The reciprocal of a fraction is created by swapping numerator and denominator. The reciprocal of 3/4 is 4/3. The reciprocal of 5 (= 5/1) is 1/5. Important: 0 has no reciprocal!

Dividing Fractions

**Rule:** Multiply by the reciprocal of the second fraction.

**Example:** 2/3 ÷ 4/5 = 2/3 × 5/4 = 10/12 = 5/6.

**Why does this work?** Division is the inverse operation of multiplication. 'Dividing by 4/5' is the same as 'multiplying by 5/4'.

Common Mistakes

1. Forgetting to take the reciprocal when dividing.

2. Flipping both fractions instead of just the second one.

3. Not simplifying the result.

Multiplying/Dividing Mixed Numbers

Convert mixed numbers to improper fractions first: 1 1/2 × 2 1/3 = 3/2 × 7/3 = 21/6 = 7/2 = 3 1/2.

Our Fraction Calculator

In the 'Basic Operations' tab, you can calculate multiplication and division instantly. Switch between +, -, × and ÷ with one click!