Add 4/42 and 21/27, Solve 4/42 + 21/27 as a fraction

Add 4/42 and 21/27

4/42 + 21/27 is 55/63.

Find the least common denominator or LCM of the two denominators:
LCM of 42 and 27 is 378

Next, find the equivalent fraction of both fractional numbers with denominator 378
For the 1st fraction, since 42 × 9 = 378,
4/42 = 4 × 9/42 × 9 = 36/378
Likewise, for the 2nd fraction, since 27 × 14 = 378,
21/27 = 21 × 14/27 × 14 = 294/378
Add the two like fractions:
36/378 + 294/378 = 36 + 294/378 = 330/378
330/378 simplified gives 55/63
So, 4/42 + 21/27 = 55/63

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