Add 7/15 and 42/81, Solve 7/15 + 42/81 as a fraction

Add 7/15 and 42/81

7/15 + 42/81 is 133/135.

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,
7/15 = 7 × 27/15 × 27 = 189/405
Likewise, for the 2nd fraction, since 81 × 5 = 405,
42/81 = 42 × 5/81 × 5 = 210/405
Add the two like fractions:
189/405 + 210/405 = 189 + 210/405 = 399/405
399/405 simplified gives 133/135
So, 7/15 + 42/81 = 133/135

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