Add 21/63 and 5/4, Solve 21/63 + 1 1/4 as a fraction

Add 21/63 and 5/4

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

21/63 + 5/4 is 19/12.

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

Next, find the equivalent fraction of both fractional numbers with denominator 252
For the 1st fraction, since 63 × 4 = 252,
21/63 = 21 × 4/63 × 4 = 84/252
Likewise, for the 2nd fraction, since 4 × 63 = 252,
5/4 = 5 × 63/4 × 63 = 315/252
Add the two like fractions:
84/252 + 315/252 = 84 + 315/252 = 399/252
399/252 simplified gives 19/12
So, 21/63 + 5/4 = 19/12
In mixed form: 17/12

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