Add 21/54 and 63/12, Solve 21/54 + 5 3/12 as a fraction

Add 21/54 and 63/12

1^st number: 21/54, 2^nd number: 5 3/12

21/54 + 63/12 is 203/36.

Find the least common denominator or LCM of the two denominators:
LCM of 54 and 12 is 108

Next, find the equivalent fraction of both fractional numbers with denominator 108
For the 1st fraction, since 54 × 2 = 108,
21/54 = 21 × 2/54 × 2 = 42/108
Likewise, for the 2nd fraction, since 12 × 9 = 108,
63/12 = 63 × 9/12 × 9 = 567/108
Add the two like fractions:
42/108 + 567/108 = 42 + 567/108 = 609/108
609/108 simplified gives 203/36
So, 21/54 + 63/12 = 203/36
In mixed form: 523/36

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