Add 21/28 and 25/30
21/28 + 25/30 is 19/12.
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,
25/30 = 25 × 14/30 × 14 = 350/420 - Add the two like fractions:
315/420 + 350/420 = 315 + 350/420 = 665/420 - 665/420 simplified gives 19/12
- So, 21/28 + 25/30 = 19/12
In mixed form: 17/12
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