Add 21/63 and 42/49
21/63 + 42/49 is 25/21.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 63 and 49 is 441
Next, find the equivalent fraction of both fractional numbers with denominator 441 - For the 1st fraction, since 63 × 7 = 441,
21/63 = 21 × 7/63 × 7 = 147/441 - Likewise, for the 2nd fraction, since 49 × 9 = 441,
42/49 = 42 × 9/49 × 9 = 378/441 - Add the two like fractions:
147/441 + 378/441 = 147 + 378/441 = 525/441 - 525/441 simplified gives 25/21
- So, 21/63 + 42/49 = 25/21
In mixed form: 14/21
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