Add 21/42 and 42/27, Solve 21/42 + 1 15/27 as a fraction

Add 21/42 and 42/27

1^st number: 21/42, 2^nd number: 1 15/27

21/42 + 42/27 is 37/18.

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,
21/42 = 21 × 9/42 × 9 = 189/378
Likewise, for the 2nd fraction, since 27 × 14 = 378,
42/27 = 42 × 14/27 × 14 = 588/378
Add the two like fractions:
189/378 + 588/378 = 189 + 588/378 = 777/378
777/378 simplified gives 37/18
So, 21/42 + 42/27 = 37/18
In mixed form: 21/18

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