Add 12/54 and 42/21, Solve 12/54 + 2 0/21 as a fraction

Add 12/54 and 42/21

1^st number: 12/54, 2^nd number: 2 0/21

12/54 + 42/21 is 20/9.

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,
42/21 = 42 × 18/21 × 18 = 756/378
Add the two like fractions:
84/378 + 756/378 = 84 + 756/378 = 840/378
840/378 simplified gives 20/9
So, 12/54 + 42/21 = 20/9
In mixed form: 22/9

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