Add 21/8 and 90/15
1st number: 2 5/8, 2nd number: 6 0/15
21/8 + 90/15 is 69/8.
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,
90/15 = 90 × 8/15 × 8 = 720/120 - Add the two like fractions:
315/120 + 720/120 = 315 + 720/120 = 1035/120 - 1035/120 simplified gives 69/8
- So, 21/8 + 90/15 = 69/8
In mixed form: 85/8
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