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

Add 81/54 and 27/42

1^st number: 1 27/54, 2^nd number: 27/42

81/54 + 27/42 is 15/7.

Find the least common denominator or LCM of the two denominators:
LCM of 54 and 42 is 378

Next, find the equivalent fraction of both fractional numbers with denominator 378
For the 1st fraction, since 54 × 7 = 378,
81/54 = 81 × 7/54 × 7 = 567/378
Likewise, for the 2nd fraction, since 42 × 9 = 378,
27/42 = 27 × 9/42 × 9 = 243/378
Add the two like fractions:
567/378 + 243/378 = 567 + 243/378 = 810/378
810/378 simplified gives 15/7
So, 81/54 + 27/42 = 15/7
In mixed form: 21/7

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