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

Add 42/21 and 12/54

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

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

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,
42/21 = 42 × 18/21 × 18 = 756/378
Likewise, for the 2nd fraction, since 54 × 7 = 378,
12/54 = 12 × 7/54 × 7 = 84/378
Add the two like fractions:
756/378 + 84/378 = 756 + 84/378 = 840/378
840/378 simplified gives 20/9
So, 42/21 + 12/54 = 20/9
In mixed form: 22/9

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