Add 15/42 and 15/54, Solve 15/42 + 15/54 as a fraction

Add 15/42 and 15/54

15/42 + 15/54 is 40/63.

Find the least common denominator or LCM of the two denominators:
LCM of 42 and 54 is 378

Next, find the equivalent fraction of both fractional numbers with denominator 378
For the 1st fraction, since 42 × 9 = 378,
15/42 = 15 × 9/42 × 9 = 135/378
Likewise, for the 2nd fraction, since 54 × 7 = 378,
15/54 = 15 × 7/54 × 7 = 105/378
Add the two like fractions:
135/378 + 105/378 = 135 + 105/378 = 240/378
240/378 simplified gives 40/63
So, 15/42 + 15/54 = 40/63

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