Add 15/12 and 21/63, Solve 1 3/12 + 21/63 as a fraction

Add 15/12 and 21/63

1^st number: 1 3/12, 2^nd number: 21/63

15/12 + 21/63 is 19/12.

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,
15/12 = 15 × 21/12 × 21 = 315/252
Likewise, for the 2nd fraction, since 63 × 4 = 252,
21/63 = 21 × 4/63 × 4 = 84/252
Add the two like fractions:
315/252 + 84/252 = 315 + 84/252 = 399/252
399/252 simplified gives 19/12
So, 15/12 + 21/63 = 19/12
In mixed form: 17/12

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