Add 21/28 and 15/30
21/28 + 15/30 is 5/4.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 28 and 30 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 30 × 14 = 420,
15/30 = 15 × 14/30 × 14 = 210/420 - Add the two like fractions:
315/420 + 210/420 = 315 + 210/420 = 525/420 - 525/420 simplified gives 5/4
- So, 21/28 + 15/30 = 5/4
In mixed form: 11/4
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