Add 12/81 and 21/9, Solve 12/81 + 2 3/9 as a fraction

Add 12/81 and 21/9

1^st number: 12/81, 2^nd number: 2 3/9

12/81 + 21/9 is 67/27.

Find the least common denominator or LCM of the two denominators:
LCM of 81 and 9 is 81

Next, find the equivalent fraction of both fractional numbers with denominator 81
For the 1st fraction, since 81 × 1 = 81,
12/81 = 12 × 1/81 × 1 = 12/81
Likewise, for the 2nd fraction, since 9 × 9 = 81,
21/9 = 21 × 9/9 × 9 = 189/81
Add the two like fractions:
12/81 + 189/81 = 12 + 189/81 = 201/81
201/81 simplified gives 67/27
So, 12/81 + 21/9 = 67/27
In mixed form: 213/27

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