Add 72/21 and 8/54, Solve 3 9/21 + 8/54 as a fraction

Add 72/21 and 8/54

1^st number: 3 9/21, 2^nd number: 8/54

72/21 + 8/54 is 676/189.

Find the least common denominator or LCM of the two denominators:
LCM of 21 and 54 is 378

Next, find the equivalent fraction of both fractional numbers with denominator 378
For the 1st fraction, since 21 × 18 = 378,
72/21 = 72 × 18/21 × 18 = 1296/378
Likewise, for the 2nd fraction, since 54 × 7 = 378,
8/54 = 8 × 7/54 × 7 = 56/378
Add the two like fractions:
1296/378 + 56/378 = 1296 + 56/378 = 1352/378
1352/378 simplified gives 676/189
So, 72/21 + 8/54 = 676/189
In mixed form: 3109/189

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