Add 36/42 and 45/12, Solve 36/42 + 3 9/12 as a fraction

Add 36/42 and 45/12

1^st number: 36/42, 2^nd number: 3 9/12

36/42 + 45/12 is 129/28.

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,
36/42 = 36 × 2/42 × 2 = 72/84
Likewise, for the 2nd fraction, since 12 × 7 = 84,
45/12 = 45 × 7/12 × 7 = 315/84
Add the two like fractions:
72/84 + 315/84 = 72 + 315/84 = 387/84
387/84 simplified gives 129/28
So, 36/42 + 45/12 = 129/28
In mixed form: 417/28

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