Add 14/15 and 21/81, Solve 14/15 + 21/81 as a fraction

Add 14/15 and 21/81

14/15 + 21/81 is 161/135.

Find the least common denominator or LCM of the two denominators:
LCM of 15 and 81 is 405

Next, find the equivalent fraction of both fractional numbers with denominator 405
For the 1st fraction, since 15 × 27 = 405,
14/15 = 14 × 27/15 × 27 = 378/405
Likewise, for the 2nd fraction, since 81 × 5 = 405,
21/81 = 21 × 5/81 × 5 = 105/405
Add the two like fractions:
378/405 + 105/405 = 378 + 105/405 = 483/405
483/405 simplified gives 161/135
So, 14/15 + 21/81 = 161/135
In mixed form: 126/135

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