Add 21/12 and 3/81, Solve 1 9/12 + 3/81 as a fraction

Add 21/12 and 3/81

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

21/12 + 3/81 is 193/108.

Find the least common denominator or LCM of the two denominators:
LCM of 12 and 81 is 324

Next, find the equivalent fraction of both fractional numbers with denominator 324
For the 1st fraction, since 12 × 27 = 324,
21/12 = 21 × 27/12 × 27 = 567/324
Likewise, for the 2nd fraction, since 81 × 4 = 324,
3/81 = 3 × 4/81 × 4 = 12/324
Add the two like fractions:
567/324 + 12/324 = 567 + 12/324 = 579/324
579/324 simplified gives 193/108
So, 21/12 + 3/81 = 193/108
In mixed form: 185/108

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