Add 28/81 and 12/5, Solve 28/81 + 2 2/5 as a fraction

Add 28/81 and 12/5

1^st number: 28/81, 2^nd number: 2 2/5

28/81 + 12/5 is 1112/405.

Find the least common denominator or LCM of the two denominators:
LCM of 81 and 5 is 405

Next, find the equivalent fraction of both fractional numbers with denominator 405
For the 1st fraction, since 81 × 5 = 405,
28/81 = 28 × 5/81 × 5 = 140/405
Likewise, for the 2nd fraction, since 5 × 81 = 405,
12/5 = 12 × 81/5 × 81 = 972/405
Add the two like fractions:
140/405 + 972/405 = 140 + 972/405 = 1112/405
So, 28/81 + 12/5 = 1112/405
In mixed form: 2302/405

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