Add 81/15 and 21/28
1st number: 5 6/15, 2nd number: 21/28
81/15 + 21/28 is 123/20.
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,
81/15 = 81 × 28/15 × 28 = 2268/420 - Likewise, for the 2nd fraction, since 28 × 15 = 420,
21/28 = 21 × 15/28 × 15 = 315/420 - Add the two like fractions:
2268/420 + 315/420 = 2268 + 315/420 = 2583/420 - 2583/420 simplified gives 123/20
- So, 81/15 + 21/28 = 123/20
In mixed form: 63/20
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