Add 21/28 and 5/15
21/28 + 5/15 is 13/12.
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,
21/28 = 21 × 15/28 × 15 = 315/420 - Likewise, for the 2nd fraction, since 15 × 28 = 420,
5/15 = 5 × 28/15 × 28 = 140/420 - Add the two like fractions:
315/420 + 140/420 = 315 + 140/420 = 455/420 - 455/420 simplified gives 13/12
- So, 21/28 + 5/15 = 13/12
In mixed form: 11/12
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