Add 4/12 and 21/27, Solve 4/12 + 21/27 as a fraction

Add 4/12 and 21/27

4/12 + 21/27 is 10/9.

Find the least common denominator or LCM of the two denominators:
LCM of 12 and 27 is 108

Next, find the equivalent fraction of both fractional numbers with denominator 108
For the 1st fraction, since 12 × 9 = 108,
4/12 = 4 × 9/12 × 9 = 36/108
Likewise, for the 2nd fraction, since 27 × 4 = 108,
21/27 = 21 × 4/27 × 4 = 84/108
Add the two like fractions:
36/108 + 84/108 = 36 + 84/108 = 120/108
120/108 simplified gives 10/9
So, 4/12 + 21/27 = 10/9
In mixed form: 11/9

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