Add 21/42 and 54/21, Solve 21/42 + 2 12/21 as a fraction

Add 21/42 and 54/21

1^st number: 21/42, 2^nd number: 2 12/21

21/42 + 54/21 is 43/14.

Find the least common denominator or LCM of the two denominators:
LCM of 42 and 21 is 42

Next, find the equivalent fraction of both fractional numbers with denominator 42
For the 1st fraction, since 42 × 1 = 42,
21/42 = 21 × 1/42 × 1 = 21/42
Likewise, for the 2nd fraction, since 21 × 2 = 42,
54/21 = 54 × 2/21 × 2 = 108/42
Add the two like fractions:
21/42 + 108/42 = 21 + 108/42 = 129/42
129/42 simplified gives 43/14
So, 21/42 + 54/21 = 43/14
In mixed form: 31/14

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