Add 45/12 and 56/42, Solve 3 9/12 + 1 14/42 as a fraction

Add 45/12 and 56/42

1^st number: 3 9/12, 2^nd number: 1 14/42

45/12 + 56/42 is 61/12.

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,
45/12 = 45 × 7/12 × 7 = 315/84
Likewise, for the 2nd fraction, since 42 × 2 = 84,
56/42 = 56 × 2/42 × 2 = 112/84
Add the two like fractions:
315/84 + 112/84 = 315 + 112/84 = 427/84
427/84 simplified gives 61/12
So, 45/12 + 56/42 = 61/12
In mixed form: 51/12

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