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

Add 12/4 and 3/21

1^st number: 3 0/4, 2^nd number: 3/21

12/4 + 3/21 is 22/7.

Find the least common denominator or LCM of the two denominators:
LCM of 4 and 21 is 84

Next, find the equivalent fraction of both fractional numbers with denominator 84
For the 1st fraction, since 4 × 21 = 84,
12/4 = 12 × 21/4 × 21 = 252/84
Likewise, for the 2nd fraction, since 21 × 4 = 84,
3/21 = 3 × 4/21 × 4 = 12/84
Add the two like fractions:
252/84 + 12/84 = 252 + 12/84 = 264/84
264/84 simplified gives 22/7
So, 12/4 + 3/21 = 22/7
In mixed form: 31/7

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