Add 21/12 and 45/63
1st number: 1 9/12, 2nd number: 45/63
21/12 + 45/63 is 69/28.
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,
45/63 = 45 × 4/63 × 4 = 180/252 - Add the two like fractions:
441/252 + 180/252 = 441 + 180/252 = 621/252 - 621/252 simplified gives 69/28
- So, 21/12 + 45/63 = 69/28
In mixed form: 213/28
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