Add 81/27 and 54/42, Solve 3 0/27 + 1 12/42 as a fraction

Add 81/27 and 54/42

1^st number: 3 0/27, 2^nd number: 1 12/42

81/27 + 54/42 is 30/7.

Find the least common denominator or LCM of the two denominators:
LCM of 27 and 42 is 378

Next, find the equivalent fraction of both fractional numbers with denominator 378
For the 1st fraction, since 27 × 14 = 378,
81/27 = 81 × 14/27 × 14 = 1134/378
Likewise, for the 2nd fraction, since 42 × 9 = 378,
54/42 = 54 × 9/42 × 9 = 486/378
Add the two like fractions:
1134/378 + 486/378 = 1134 + 486/378 = 1620/378
1620/378 simplified gives 30/7
So, 81/27 + 54/42 = 30/7
In mixed form: 42/7

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