Add 15/21 and 63/12, Solve 15/21 + 5 3/12 as a fraction

Add 15/21 and 63/12

1^st number: 15/21, 2^nd number: 5 3/12

15/21 + 63/12 is 167/28.

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

Next, find the equivalent fraction of both fractional numbers with denominator 84
For the 1st fraction, since 21 × 4 = 84,
15/21 = 15 × 4/21 × 4 = 60/84
Likewise, for the 2nd fraction, since 12 × 7 = 84,
63/12 = 63 × 7/12 × 7 = 441/84
Add the two like fractions:
60/84 + 441/84 = 60 + 441/84 = 501/84
501/84 simplified gives 167/28
So, 15/21 + 63/12 = 167/28
In mixed form: 527/28

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