Add 81/30 and 27/12, Solve 2 21/30 + 2 3/12 as a fraction

Add 81/30 and 27/12

1^st number: 2 21/30, 2^nd number: 2 3/12

81/30 + 27/12 is 99/20.

Find the least common denominator or LCM of the two denominators:
LCM of 30 and 12 is 60

Next, find the equivalent fraction of both fractional numbers with denominator 60
For the 1st fraction, since 30 × 2 = 60,
81/30 = 81 × 2/30 × 2 = 162/60
Likewise, for the 2nd fraction, since 12 × 5 = 60,
27/12 = 27 × 5/12 × 5 = 135/60
Add the two like fractions:
162/60 + 135/60 = 162 + 135/60 = 297/60
297/60 simplified gives 99/20
So, 81/30 + 27/12 = 99/20
In mixed form: 419/20

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