Add 21/12 and 90/63
1st number: 1 9/12, 2nd number: 1 27/63
21/12 + 90/63 is 89/28.
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,
90/63 = 90 × 4/63 × 4 = 360/252 - Add the two like fractions:
441/252 + 360/252 = 441 + 360/252 = 801/252 - 801/252 simplified gives 89/28
- So, 21/12 + 90/63 = 89/28
In mixed form: 35/28
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