Add 54/21 and 25/42, Solve 2 12/21 + 25/42 as a fraction

Add 54/21 and 25/42

1^st number: 2 12/21, 2^nd number: 25/42

54/21 + 25/42 is 19/6.

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

Next, find the equivalent fraction of both fractional numbers with denominator 42
For the 1st fraction, since 21 × 2 = 42,
54/21 = 54 × 2/21 × 2 = 108/42
Likewise, for the 2nd fraction, since 42 × 1 = 42,
25/42 = 25 × 1/42 × 1 = 25/42
Add the two like fractions:
108/42 + 25/42 = 108 + 25/42 = 133/42
133/42 simplified gives 19/6
So, 54/21 + 25/42 = 19/6
In mixed form: 31/6

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