Add 10/54 and 72/21, Solve 10/54 + 3 9/21 as a fraction

Add 10/54 and 72/21

1^st number: 10/54, 2^nd number: 3 9/21

10/54 + 72/21 is 683/189.

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

Next, find the equivalent fraction of both fractional numbers with denominator 378
For the 1st fraction, since 54 × 7 = 378,
10/54 = 10 × 7/54 × 7 = 70/378
Likewise, for the 2nd fraction, since 21 × 18 = 378,
72/21 = 72 × 18/21 × 18 = 1296/378
Add the two like fractions:
70/378 + 1296/378 = 70 + 1296/378 = 1366/378
1366/378 simplified gives 683/189
So, 10/54 + 72/21 = 683/189
In mixed form: 3116/189

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