Add 21/8 and 12/15
1st number: 2 5/8, 2nd number: 12/15
21/8 + 12/15 is 137/40.
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,
21/8 = 21 × 15/8 × 15 = 315/120 - Likewise, for the 2nd fraction, since 15 × 8 = 120,
12/15 = 12 × 8/15 × 8 = 96/120 - Add the two like fractions:
315/120 + 96/120 = 315 + 96/120 = 411/120 - 411/120 simplified gives 137/40
- So, 21/8 + 12/15 = 137/40
In mixed form: 317/40
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