Add 12/42 and 15/12, Solve 12/42 + 1 3/12 as a fraction

Add 12/42 and 15/12

1^st number: 12/42, 2^nd number: 1 3/12

12/42 + 15/12 is 43/28.

Find the least common denominator or LCM of the two denominators:
LCM of 42 and 12 is 84

Next, find the equivalent fraction of both fractional numbers with denominator 84
For the 1st fraction, since 42 × 2 = 84,
12/42 = 12 × 2/42 × 2 = 24/84
Likewise, for the 2nd fraction, since 12 × 7 = 84,
15/12 = 15 × 7/12 × 7 = 105/84
Add the two like fractions:
24/84 + 105/84 = 24 + 105/84 = 129/84
129/84 simplified gives 43/28
So, 12/42 + 15/12 = 43/28
In mixed form: 115/28

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