Add 72/12 and 90/42, Solve 6 0/12 + 2 6/42 as a fraction

Add 72/12 and 90/42

1^st number: 6 0/12, 2^nd number: 2 6/42

72/12 + 90/42 is 57/7.

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,
72/12 = 72 × 7/12 × 7 = 504/84
Likewise, for the 2nd fraction, since 42 × 2 = 84,
90/42 = 90 × 2/42 × 2 = 180/84
Add the two like fractions:
504/84 + 180/84 = 504 + 180/84 = 684/84
684/84 simplified gives 57/7
So, 72/12 + 90/42 = 57/7
In mixed form: 81/7

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