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

Add 84/21 and 21/54

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

84/21 + 21/54 is 79/18.

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,
21/54 = 21 × 7/54 × 7 = 147/378
Add the two like fractions:
1512/378 + 147/378 = 1512 + 147/378 = 1659/378
1659/378 simplified gives 79/18
So, 84/21 + 21/54 = 79/18
In mixed form: 47/18

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