Add 84/21 and 42/54, Solve 4 0/21 + 42/54 as a fraction

Add 84/21 and 42/54

1^st number: 4 0/21, 2^nd number: 42/54

84/21 + 42/54 is 43/9.

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,
84/21 = 84 × 18/21 × 18 = 1512/378
Likewise, for the 2nd fraction, since 54 × 7 = 378,
42/54 = 42 × 7/54 × 7 = 294/378
Add the two like fractions:
1512/378 + 294/378 = 1512 + 294/378 = 1806/378
1806/378 simplified gives 43/9
So, 84/21 + 42/54 = 43/9
In mixed form: 47/9

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