Add 7/8 and 15/21
7/8 + 15/21 is 89/56.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 8 and 21 is 168
Next, find the equivalent fraction of both fractional numbers with denominator 168 - For the 1st fraction, since 8 × 21 = 168,
7/8 = 7 × 21/8 × 21 = 147/168 - Likewise, for the 2nd fraction, since 21 × 8 = 168,
15/21 = 15 × 8/21 × 8 = 120/168 - Add the two like fractions:
147/168 + 120/168 = 147 + 120/168 = 267/168 - 267/168 simplified gives 89/56
- So, 7/8 + 15/21 = 89/56
In mixed form: 133/56
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