Add 54/21 and 27/12, Solve 2 12/21 + 2 3/12 as a fraction

Add 54/21 and 27/12

1^st number: 2 12/21, 2^nd number: 2 3/12

54/21 + 27/12 is 135/28.

Find the least common denominator or LCM of the two denominators:
LCM of 21 and 12 is 84

Next, find the equivalent fraction of both fractional numbers with denominator 84
For the 1st fraction, since 21 × 4 = 84,
54/21 = 54 × 4/21 × 4 = 216/84
Likewise, for the 2nd fraction, since 12 × 7 = 84,
27/12 = 27 × 7/12 × 7 = 189/84
Add the two like fractions:
216/84 + 189/84 = 216 + 189/84 = 405/84
405/84 simplified gives 135/28
So, 54/21 + 27/12 = 135/28
In mixed form: 423/28

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