Add 15/4 and 21/63, Solve 3 3/4 + 21/63 as a fraction

Add 15/4 and 21/63

1^st number: 3 3/4, 2^nd number: 21/63

15/4 + 21/63 is 49/12.

Find the least common denominator or LCM of the two denominators:
LCM of 4 and 63 is 252

Next, find the equivalent fraction of both fractional numbers with denominator 252
For the 1st fraction, since 4 × 63 = 252,
15/4 = 15 × 63/4 × 63 = 945/252
Likewise, for the 2nd fraction, since 63 × 4 = 252,
21/63 = 21 × 4/63 × 4 = 84/252
Add the two like fractions:
945/252 + 84/252 = 945 + 84/252 = 1029/252
1029/252 simplified gives 49/12
So, 15/4 + 21/63 = 49/12
In mixed form: 41/12

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