Add 20/42 and 15/18, Solve 20/42 + 15/18 as a fraction

Add 20/42 and 15/18

20/42 + 15/18 is 55/42.

Find the least common denominator or LCM of the two denominators:
LCM of 42 and 18 is 126

Next, find the equivalent fraction of both fractional numbers with denominator 126
For the 1st fraction, since 42 × 3 = 126,
20/42 = 20 × 3/42 × 3 = 60/126
Likewise, for the 2nd fraction, since 18 × 7 = 126,
15/18 = 15 × 7/18 × 7 = 105/126
Add the two like fractions:
60/126 + 105/126 = 60 + 105/126 = 165/126
165/126 simplified gives 55/42
So, 20/42 + 15/18 = 55/42
In mixed form: 113/42

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