Add 21/15 and 15/12
1st number: 1 6/15, 2nd number: 1 3/12
21/15 + 15/12 is 53/20.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 15 and 12 is 60
Next, find the equivalent fraction of both fractional numbers with denominator 60 - For the 1st fraction, since 15 × 4 = 60,
21/15 = 21 × 4/15 × 4 = 84/60 - Likewise, for the 2nd fraction, since 12 × 5 = 60,
15/12 = 15 × 5/12 × 5 = 75/60 - Add the two like fractions:
84/60 + 75/60 = 84 + 75/60 = 159/60 - 159/60 simplified gives 53/20
- So, 21/15 + 15/12 = 53/20
In mixed form: 213/20
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