Add 20/42 and 45/54, Solve 20/42 + 45/54 as a fraction

Add 20/42 and 45/54

20/42 + 45/54 is 55/42.

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,
20/42 = 20 × 9/42 × 9 = 180/378
Likewise, for the 2nd fraction, since 54 × 7 = 378,
45/54 = 45 × 7/54 × 7 = 315/378
Add the two like fractions:
180/378 + 315/378 = 180 + 315/378 = 495/378
495/378 simplified gives 55/42
So, 20/42 + 45/54 = 55/42
In mixed form: 113/42

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