Add 4/12 and 21/7, Solve 4/12 + 3 0/7 as a fraction

Add 4/12 and 21/7

1^st number: 4/12, 2^nd number: 3 0/7

4/12 + 21/7 is 10/3.

Find the least common denominator or LCM of the two denominators:
LCM of 12 and 7 is 84

Next, find the equivalent fraction of both fractional numbers with denominator 84
For the 1st fraction, since 12 × 7 = 84,
4/12 = 4 × 7/12 × 7 = 28/84
Likewise, for the 2nd fraction, since 7 × 12 = 84,
21/7 = 21 × 12/7 × 12 = 252/84
Add the two like fractions:
28/84 + 252/84 = 28 + 252/84 = 280/84
280/84 simplified gives 10/3
So, 4/12 + 21/7 = 10/3
In mixed form: 31/3

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