Add 20/12 and 4/81, Solve 1 8/12 + 4/81 as a fraction

Add 20/12 and 4/81

1^st number: 1 8/12, 2^nd number: 4/81

20/12 + 4/81 is 139/81.

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,
20/12 = 20 × 27/12 × 27 = 540/324
Likewise, for the 2nd fraction, since 81 × 4 = 324,
4/81 = 4 × 4/81 × 4 = 16/324
Add the two like fractions:
540/324 + 16/324 = 540 + 16/324 = 556/324
556/324 simplified gives 139/81
So, 20/12 + 4/81 = 139/81
In mixed form: 158/81

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