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

Add 12/54 and 5/21

12/54 + 5/21 is 29/63.

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,
12/54 = 12 × 7/54 × 7 = 84/378
Likewise, for the 2nd fraction, since 21 × 18 = 378,
5/21 = 5 × 18/21 × 18 = 90/378
Add the two like fractions:
84/378 + 90/378 = 84 + 90/378 = 174/378
174/378 simplified gives 29/63
So, 12/54 + 5/21 = 29/63

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