Add 12/21 and 81/36, Solve 12/21 + 2 9/36 as a fraction

Add 12/21 and 81/36

1^st number: 12/21, 2^nd number: 2 9/36

12/21 + 81/36 is 79/28.

Find the least common denominator or LCM of the two denominators:
LCM of 21 and 36 is 252

Next, find the equivalent fraction of both fractional numbers with denominator 252
For the 1st fraction, since 21 × 12 = 252,
12/21 = 12 × 12/21 × 12 = 144/252
Likewise, for the 2nd fraction, since 36 × 7 = 252,
81/36 = 81 × 7/36 × 7 = 567/252
Add the two like fractions:
144/252 + 567/252 = 144 + 567/252 = 711/252
711/252 simplified gives 79/28
So, 12/21 + 81/36 = 79/28
In mixed form: 223/28

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