Multiplying
Multiply the tops and multiply the bottoms, then simplify: 2/3 × 3/5 = 6/15 = 2/5. You can cancel first to keep the numbers small.
Mixed numbers must become improper fractions first: 2 1/3 × 1 1/2 = 7/3 × 3/2 = 21/6 = 3 1/2. Multiplying the whole numbers and the fractions separately (2 × 1 and 1/3 × 1/2) misses part of the answer.
Dividing
The reciprocal of a fraction is the fraction flipped: the reciprocal of 3/4 is 4/3, and of 5 is 1/5. Dividing by a fraction is the same as multiplying by its reciprocal.
- 3/4 ÷ 2/5
- = 3/4 × 5/2
- = 15/8 = 1 7/8
How many 3/4 m pieces can be cut from 6 m of ribbon? 6 ÷ 3/4 = 6 × 4/3 = 8 pieces.
Divide on the calculator
Enter 3 1/2 ÷ 1 3/4 in the fraction calculator. Before you press, predict: is the answer more or less than 3 1/2? Then try 3 1/2 ÷ 3/4.