Add 27/12 and 21/7, Solve 2 3/12 + 3 0/7 as a fraction

Add 27/12 and 21/7

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

27/12 + 21/7 is 21/4.

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,
27/12 = 27 × 7/12 × 7 = 189/84
Likewise, for the 2nd fraction, since 7 × 12 = 84,
21/7 = 21 × 12/7 × 12 = 252/84
Add the two like fractions:
189/84 + 252/84 = 189 + 252/84 = 441/84
441/84 simplified gives 21/4
So, 27/12 + 21/7 = 21/4
In mixed form: 51/4

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