Add 12/28 and 84/21, Solve 12/28 + 4 0/21 as a fraction

Add 12/28 and 84/21

1^st number: 12/28, 2^nd number: 4 0/21

12/28 + 84/21 is 31/7.

Find the least common denominator or LCM of the two denominators:
LCM of 28 and 21 is 84

Next, find the equivalent fraction of both fractional numbers with denominator 84
For the 1st fraction, since 28 × 3 = 84,
12/28 = 12 × 3/28 × 3 = 36/84
Likewise, for the 2nd fraction, since 21 × 4 = 84,
84/21 = 84 × 4/21 × 4 = 336/84
Add the two like fractions:
36/84 + 336/84 = 36 + 336/84 = 372/84
372/84 simplified gives 31/7
So, 12/28 + 84/21 = 31/7
In mixed form: 43/7

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