Add 15/12 and 35/42, Solve 1 3/12 + 35/42 as a fraction

Add 15/12 and 35/42

1^st number: 1 3/12, 2^nd number: 35/42

15/12 + 35/42 is 25/12.

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

Next, find the equivalent fraction of both fractional numbers with denominator 84
For the 1st fraction, since 12 × 7 = 84,
15/12 = 15 × 7/12 × 7 = 105/84
Likewise, for the 2nd fraction, since 42 × 2 = 84,
35/42 = 35 × 2/42 × 2 = 70/84
Add the two like fractions:
105/84 + 70/84 = 105 + 70/84 = 175/84
175/84 simplified gives 25/12
So, 15/12 + 35/42 = 25/12
In mixed form: 21/12

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