Add 21/15 and 81/8
1st number: 1 6/15, 2nd number: 10 1/8
21/15 + 81/8 is 461/40.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 15 and 8 is 120
Next, find the equivalent fraction of both fractional numbers with denominator 120 - For the 1st fraction, since 15 × 8 = 120,
21/15 = 21 × 8/15 × 8 = 168/120 - Likewise, for the 2nd fraction, since 8 × 15 = 120,
81/8 = 81 × 15/8 × 15 = 1215/120 - Add the two like fractions:
168/120 + 1215/120 = 168 + 1215/120 = 1383/120 - 1383/120 simplified gives 461/40
- So, 21/15 + 81/8 = 461/40
In mixed form: 1121/40
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