Fractions

Two fractions are equivalent when they describe the same amount. To find an equivalent fraction, multiply the top and bottom by the same number. To turn 3/4 into twentieths, note 20 ÷ 4 = 5, so multiply both parts by 5: 3 × 5 = 15. That gives 3/4 = 15/20.

To add or subtract, first give both fractions the same denominator. For 1/4 + 1/2, rewrite 1/2 as 2/4. Then 1/4 + 2/4 = 3/4.

Subtraction works the same way. For 5/6 − 1/3, rewrite 1/3 as 2/6. Then 5/6 − 2/6 = 3/6 = 1/2.

To find a fraction of an amount, divide by the denominator and multiply by the numerator. For 2/5 of 30: 30 ÷ 5 = 6, then 6 × 2 = 12.