Add 21/28 and 7/63
21/28 + 7/63 is 31/36.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 28 and 63 is 252
Next, find the equivalent fraction of both fractional numbers with denominator 252 - For the 1st fraction, since 28 × 9 = 252,
21/28 = 21 × 9/28 × 9 = 189/252 - Likewise, for the 2nd fraction, since 63 × 4 = 252,
7/63 = 7 × 4/63 × 4 = 28/252 - Add the two like fractions:
189/252 + 28/252 = 189 + 28/252 = 217/252 - 217/252 simplified gives 31/36
- So, 21/28 + 7/63 = 31/36
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