Add 12/18 and 81/42, Solve 12/18 + 1 39/42 as a fraction

Add 12/18 and 81/42

1^st number: 12/18, 2^nd number: 1 39/42

12/18 + 81/42 is 109/42.

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

Next, find the equivalent fraction of both fractional numbers with denominator 126
For the 1st fraction, since 18 × 7 = 126,
12/18 = 12 × 7/18 × 7 = 84/126
Likewise, for the 2nd fraction, since 42 × 3 = 126,
81/42 = 81 × 3/42 × 3 = 243/126
Add the two like fractions:
84/126 + 243/126 = 84 + 243/126 = 327/126
327/126 simplified gives 109/42
So, 12/18 + 81/42 = 109/42
In mixed form: 225/42

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