Add 15/8 and 9/21
1st number: 1 7/8, 2nd number: 9/21
15/8 + 9/21 is 129/56.
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,
15/8 = 15 × 21/8 × 21 = 315/168 - Likewise, for the 2nd fraction, since 21 × 8 = 168,
9/21 = 9 × 8/21 × 8 = 72/168 - Add the two like fractions:
315/168 + 72/168 = 315 + 72/168 = 387/168 - 387/168 simplified gives 129/56
- So, 15/8 + 9/21 = 129/56
In mixed form: 217/56
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