Add 27/42 and 15/18, Solve 27/42 + 15/18 as a fraction

Add 27/42 and 15/18

27/42 + 15/18 is 31/21.

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,
27/42 = 27 × 3/42 × 3 = 81/126
Likewise, for the 2nd fraction, since 18 × 7 = 126,
15/18 = 15 × 7/18 × 7 = 105/126
Add the two like fractions:
81/126 + 105/126 = 81 + 105/126 = 186/126
186/126 simplified gives 31/21
So, 27/42 + 15/18 = 31/21
In mixed form: 110/21

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