Add 12/16 and 84/21, Solve 12/16 + 4 0/21 as a fraction

Add 12/16 and 84/21

1^st number: 12/16, 2^nd number: 4 0/21

12/16 + 84/21 is 19/4.

Find the least common denominator or LCM of the two denominators:
LCM of 16 and 21 is 336

Next, find the equivalent fraction of both fractional numbers with denominator 336
For the 1st fraction, since 16 × 21 = 336,
12/16 = 12 × 21/16 × 21 = 252/336
Likewise, for the 2nd fraction, since 21 × 16 = 336,
84/21 = 84 × 16/21 × 16 = 1344/336
Add the two like fractions:
252/336 + 1344/336 = 252 + 1344/336 = 1596/336
1596/336 simplified gives 19/4
So, 12/16 + 84/21 = 19/4
In mixed form: 43/4

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