Add 72/54 and 81/42, Solve 1 18/54 + 1 39/42 as a fraction

Add 72/54 and 81/42

1^st number: 1 18/54, 2^nd number: 1 39/42

72/54 + 81/42 is 137/42.

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,
72/54 = 72 × 7/54 × 7 = 504/378
Likewise, for the 2nd fraction, since 42 × 9 = 378,
81/42 = 81 × 9/42 × 9 = 729/378
Add the two like fractions:
504/378 + 729/378 = 504 + 729/378 = 1233/378
1233/378 simplified gives 137/42
So, 72/54 + 81/42 = 137/42
In mixed form: 311/42

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