Add 15/4 and 21/54, Solve 3 3/4 + 21/54 as a fraction

Add 15/4 and 21/54

1^st number: 3 3/4, 2^nd number: 21/54

15/4 + 21/54 is 149/36.

Find the least common denominator or LCM of the two denominators:
LCM of 4 and 54 is 108

Next, find the equivalent fraction of both fractional numbers with denominator 108
For the 1st fraction, since 4 × 27 = 108,
15/4 = 15 × 27/4 × 27 = 405/108
Likewise, for the 2nd fraction, since 54 × 2 = 108,
21/54 = 21 × 2/54 × 2 = 42/108
Add the two like fractions:
405/108 + 42/108 = 405 + 42/108 = 447/108
447/108 simplified gives 149/36
So, 15/4 + 21/54 = 149/36
In mixed form: 45/36

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