Add 36/21 and 81/12, Solve 1 15/21 + 6 9/12 as a fraction

Add 36/21 and 81/12

1^st number: 1 15/21, 2^nd number: 6 9/12

36/21 + 81/12 is 237/28.

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,
81/12 = 81 × 7/12 × 7 = 567/84
Add the two like fractions:
144/84 + 567/84 = 144 + 567/84 = 711/84
711/84 simplified gives 237/28
So, 36/21 + 81/12 = 237/28
In mixed form: 813/28

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