Add 15/21 and 5/8
15/21 + 5/8 is 75/56.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 21 and 8 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 8 × 21 = 168,
5/8 = 5 × 21/8 × 21 = 105/168 - Add the two like fractions:
120/168 + 105/168 = 120 + 105/168 = 225/168 - 225/168 simplified gives 75/56
- So, 15/21 + 5/8 = 75/56
In mixed form: 119/56
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