Add 15/28 and 21/15
1st number: 15/28, 2nd number: 1 6/15
15/28 + 21/15 is 271/140.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 28 and 15 is 420
Next, find the equivalent fraction of both fractional numbers with denominator 420 - For the 1st fraction, since 28 × 15 = 420,
15/28 = 15 × 15/28 × 15 = 225/420 - Likewise, for the 2nd fraction, since 15 × 28 = 420,
21/15 = 21 × 28/15 × 28 = 588/420 - Add the two like fractions:
225/420 + 588/420 = 225 + 588/420 = 813/420 - 813/420 simplified gives 271/140
- So, 15/28 + 21/15 = 271/140
In mixed form: 1131/140
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