Add 42/63 and 21/28
42/63 + 21/28 is 17/12.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 63 and 28 is 252
Next, find the equivalent fraction of both fractional numbers with denominator 252 - For the 1st fraction, since 63 × 4 = 252,
42/63 = 42 × 4/63 × 4 = 168/252 - Likewise, for the 2nd fraction, since 28 × 9 = 252,
21/28 = 21 × 9/28 × 9 = 189/252 - Add the two like fractions:
168/252 + 189/252 = 168 + 189/252 = 357/252 - 357/252 simplified gives 17/12
- So, 42/63 + 21/28 = 17/12
In mixed form: 15/12
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