Add 20/15 and 21/28
1st number: 1 5/15, 2nd number: 21/28
20/15 + 21/28 is 25/12.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 15 and 28 is 420
Next, find the equivalent fraction of both fractional numbers with denominator 420 - For the 1st fraction, since 15 × 28 = 420,
20/15 = 20 × 28/15 × 28 = 560/420 - Likewise, for the 2nd fraction, since 28 × 15 = 420,
21/28 = 21 × 15/28 × 15 = 315/420 - Add the two like fractions:
560/420 + 315/420 = 560 + 315/420 = 875/420 - 875/420 simplified gives 25/12
- So, 20/15 + 21/28 = 25/12
In mixed form: 21/12
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