Add 84/42 and 21/54, Solve 2 0/42 + 21/54 as a fraction

Add 84/42 and 21/54

1^st number: 2 0/42, 2^nd number: 21/54

84/42 + 21/54 is 43/18.

Find the least common denominator or LCM of the two denominators:
LCM of 42 and 54 is 378

Next, find the equivalent fraction of both fractional numbers with denominator 378
For the 1st fraction, since 42 × 9 = 378,
84/42 = 84 × 9/42 × 9 = 756/378
Likewise, for the 2nd fraction, since 54 × 7 = 378,
21/54 = 21 × 7/54 × 7 = 147/378
Add the two like fractions:
756/378 + 147/378 = 756 + 147/378 = 903/378
903/378 simplified gives 43/18
So, 84/42 + 21/54 = 43/18
In mixed form: 27/18

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