Add 63/12 and 90/21, Solve 5 3/12 + 4 6/21 as a fraction

Add 63/12 and 90/21

1^st number: 5 3/12, 2^nd number: 4 6/21

63/12 + 90/21 is 267/28.

Find the least common denominator or LCM of the two denominators:
LCM of 12 and 21 is 84

Next, find the equivalent fraction of both fractional numbers with denominator 84
For the 1st fraction, since 12 × 7 = 84,
63/12 = 63 × 7/12 × 7 = 441/84
Likewise, for the 2nd fraction, since 21 × 4 = 84,
90/21 = 90 × 4/21 × 4 = 360/84
Add the two like fractions:
441/84 + 360/84 = 441 + 360/84 = 801/84
801/84 simplified gives 267/28
So, 63/12 + 90/21 = 267/28
In mixed form: 915/28

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