Add 80/42 and 15/54, Solve 1 38/42 + 15/54 as a fraction

Add 80/42 and 15/54

1^st number: 1 38/42, 2^nd number: 15/54

80/42 + 15/54 is 275/126.

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

Next, find the equivalent fraction of both fractional numbers with denominator 378
For the 1st fraction, since 42 × 9 = 378,
80/42 = 80 × 9/42 × 9 = 720/378
Likewise, for the 2nd fraction, since 54 × 7 = 378,
15/54 = 15 × 7/54 × 7 = 105/378
Add the two like fractions:
720/378 + 105/378 = 720 + 105/378 = 825/378
825/378 simplified gives 275/126
So, 80/42 + 15/54 = 275/126
In mixed form: 223/126

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