Add 81/12 and 3/42, Solve 6 9/12 + 3/42 as a fraction

Add 81/12 and 3/42

1^st number: 6 9/12, 2^nd number: 3/42

81/12 + 3/42 is 191/28.

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,
81/12 = 81 × 7/12 × 7 = 567/84
Likewise, for the 2nd fraction, since 42 × 2 = 84,
3/42 = 3 × 2/42 × 2 = 6/84
Add the two like fractions:
567/84 + 6/84 = 567 + 6/84 = 573/84
573/84 simplified gives 191/28
So, 81/12 + 3/42 = 191/28
In mixed form: 623/28

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