Add 7/8 and 21/15
1st number: 7/8, 2nd number: 1 6/15
7/8 + 21/15 is 91/40.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 8 and 15 is 120
Next, find the equivalent fraction of both fractional numbers with denominator 120 - For the 1st fraction, since 8 × 15 = 120,
7/8 = 7 × 15/8 × 15 = 105/120 - Likewise, for the 2nd fraction, since 15 × 8 = 120,
21/15 = 21 × 8/15 × 8 = 168/120 - Add the two like fractions:
105/120 + 168/120 = 105 + 168/120 = 273/120 - 273/120 simplified gives 91/40
- So, 7/8 + 21/15 = 91/40
In mixed form: 211/40
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