Add 21/42 and 49/54, Solve 21/42 + 49/54 as a fraction

Add 21/42 and 49/54

21/42 + 49/54 is 38/27.

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,
21/42 = 21 × 9/42 × 9 = 189/378
Likewise, for the 2nd fraction, since 54 × 7 = 378,
49/54 = 49 × 7/54 × 7 = 343/378
Add the two like fractions:
189/378 + 343/378 = 189 + 343/378 = 532/378
532/378 simplified gives 38/27
So, 21/42 + 49/54 = 38/27
In mixed form: 111/27

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