Add 36/21 and 90/12, Solve 1 15/21 + 7 6/12 as a fraction

Add 36/21 and 90/12

1^st number: 1 15/21, 2^nd number: 7 6/12

36/21 + 90/12 is 129/14.

Find the least common denominator or LCM of the two denominators:
LCM of 21 and 12 is 84

Next, find the equivalent fraction of both fractional numbers with denominator 84
For the 1st fraction, since 21 × 4 = 84,
36/21 = 36 × 4/21 × 4 = 144/84
Likewise, for the 2nd fraction, since 12 × 7 = 84,
90/12 = 90 × 7/12 × 7 = 630/84
Add the two like fractions:
144/84 + 630/84 = 144 + 630/84 = 774/84
774/84 simplified gives 129/14
So, 36/21 + 90/12 = 129/14
In mixed form: 93/14

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