Add 21/28 and 84/15
1st number: 21/28, 2nd number: 5 9/15
21/28 + 84/15 is 127/20.
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,
84/15 = 84 × 28/15 × 28 = 2352/420 - Add the two like fractions:
315/420 + 2352/420 = 315 + 2352/420 = 2667/420 - 2667/420 simplified gives 127/20
- So, 21/28 + 84/15 = 127/20
In mixed form: 67/20
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