Add 45/12 and 1/81, Solve 3 9/12 + 1/81 as a fraction

Add 45/12 and 1/81

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

45/12 + 1/81 is 1219/324.

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,
45/12 = 45 × 27/12 × 27 = 1215/324
Likewise, for the 2nd fraction, since 81 × 4 = 324,
1/81 = 1 × 4/81 × 4 = 4/324
Add the two like fractions:
1215/324 + 4/324 = 1215 + 4/324 = 1219/324
So, 45/12 + 1/81 = 1219/324
In mixed form: 3247/324

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