Add 81/42 and 9/12, Solve 1 39/42 + 9/12 as a fraction

Add 81/42 and 9/12

1^st number: 1 39/42, 2^nd number: 9/12

81/42 + 9/12 is 75/28.

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,
81/42 = 81 × 2/42 × 2 = 162/84
Likewise, for the 2nd fraction, since 12 × 7 = 84,
9/12 = 9 × 7/12 × 7 = 63/84
Add the two like fractions:
162/84 + 63/84 = 162 + 63/84 = 225/84
225/84 simplified gives 75/28
So, 81/42 + 9/12 = 75/28
In mixed form: 219/28

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