Add 21/63 and 9/12
21/63 + 9/12 is 13/12.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 63 and 12 is 252
Next, find the equivalent fraction of both fractional numbers with denominator 252 - For the 1st fraction, since 63 × 4 = 252,
21/63 = 21 × 4/63 × 4 = 84/252 - Likewise, for the 2nd fraction, since 12 × 21 = 252,
9/12 = 9 × 21/12 × 21 = 189/252 - Add the two like fractions:
84/252 + 189/252 = 84 + 189/252 = 273/252 - 273/252 simplified gives 13/12
- So, 21/63 + 9/12 = 13/12
In mixed form: 11/12
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