Add 54/81 and 81/42, Solve 54/81 + 1 39/42 as a fraction

Add 54/81 and 81/42

1^st number: 54/81, 2^nd number: 1 39/42

54/81 + 81/42 is 109/42.

Find the least common denominator or LCM of the two denominators:
LCM of 81 and 42 is 1134

Next, find the equivalent fraction of both fractional numbers with denominator 1134
For the 1st fraction, since 81 × 14 = 1134,
54/81 = 54 × 14/81 × 14 = 756/1134
Likewise, for the 2nd fraction, since 42 × 27 = 1134,
81/42 = 81 × 27/42 × 27 = 2187/1134
Add the two like fractions:
756/1134 + 2187/1134 = 756 + 2187/1134 = 2943/1134
2943/1134 simplified gives 109/42
So, 54/81 + 81/42 = 109/42
In mixed form: 225/42

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