Add 21/12 and 30/63
1st number: 1 9/12, 2nd number: 30/63
21/12 + 30/63 is 187/84.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 12 and 63 is 252
Next, find the equivalent fraction of both fractional numbers with denominator 252 - For the 1st fraction, since 12 × 21 = 252,
21/12 = 21 × 21/12 × 21 = 441/252 - Likewise, for the 2nd fraction, since 63 × 4 = 252,
30/63 = 30 × 4/63 × 4 = 120/252 - Add the two like fractions:
441/252 + 120/252 = 441 + 120/252 = 561/252 - 561/252 simplified gives 187/84
- So, 21/12 + 30/63 = 187/84
In mixed form: 219/84
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