Add 21/7 and 15/8
1st number: 3 0/7, 2nd number: 1 7/8
21/7 + 15/8 is 39/8.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 7 and 8 is 56
Next, find the equivalent fraction of both fractional numbers with denominator 56 - For the 1st fraction, since 7 × 8 = 56,
21/7 = 21 × 8/7 × 8 = 168/56 - Likewise, for the 2nd fraction, since 8 × 7 = 56,
15/8 = 15 × 7/8 × 7 = 105/56 - Add the two like fractions:
168/56 + 105/56 = 168 + 105/56 = 273/56 - 273/56 simplified gives 39/8
- So, 21/7 + 15/8 = 39/8
In mixed form: 47/8
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