Add 15/21 and 20/24
15/21 + 20/24 is 65/42.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 21 and 24 is 168
Next, find the equivalent fraction of both fractional numbers with denominator 168 - For the 1st fraction, since 21 × 8 = 168,
15/21 = 15 × 8/21 × 8 = 120/168 - Likewise, for the 2nd fraction, since 24 × 7 = 168,
20/24 = 20 × 7/24 × 7 = 140/168 - Add the two like fractions:
120/168 + 140/168 = 120 + 140/168 = 260/168 - 260/168 simplified gives 65/42
- So, 15/21 + 20/24 = 65/42
In mixed form: 123/42
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