Add 21/54 and 27/4, Solve 21/54 + 6 3/4 as a fraction

Add 21/54 and 27/4

1^st number: 21/54, 2^nd number: 6 3/4

21/54 + 27/4 is 257/36.

Find the least common denominator or LCM of the two denominators:
LCM of 54 and 4 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 4 × 27 = 108,
27/4 = 27 × 27/4 × 27 = 729/108
Add the two like fractions:
42/108 + 729/108 = 42 + 729/108 = 771/108
771/108 simplified gives 257/36
So, 21/54 + 27/4 = 257/36
In mixed form: 75/36

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