Add 21/49 and 42/63
21/49 + 42/63 is 23/21.
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,
42/63 = 42 × 7/63 × 7 = 294/441 - Add the two like fractions:
189/441 + 294/441 = 189 + 294/441 = 483/441 - 483/441 simplified gives 23/21
- So, 21/49 + 42/63 = 23/21
In mixed form: 12/21
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