Add 21/49 and 28/63
21/49 + 28/63 is 55/63.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 49 and 63 is 441
Next, find the equivalent fraction of both fractional numbers with denominator 441 - For the 1st fraction, since 49 × 9 = 441,
21/49 = 21 × 9/49 × 9 = 189/441 - Likewise, for the 2nd fraction, since 63 × 7 = 441,
28/63 = 28 × 7/63 × 7 = 196/441 - Add the two like fractions:
189/441 + 196/441 = 189 + 196/441 = 385/441 - 385/441 simplified gives 55/63
- So, 21/49 + 28/63 = 55/63
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