Add 7/12 and 42/21, Solve 7/12 + 2 0/21 as a fraction

Add 7/12 and 42/21

1^st number: 7/12, 2^nd number: 2 0/21

7/12 + 42/21 is 31/12.

Find the least common denominator or LCM of the two denominators:
LCM of 12 and 21 is 84

Next, find the equivalent fraction of both fractional numbers with denominator 84
For the 1st fraction, since 12 × 7 = 84,
7/12 = 7 × 7/12 × 7 = 49/84
Likewise, for the 2nd fraction, since 21 × 4 = 84,
42/21 = 42 × 4/21 × 4 = 168/84
Add the two like fractions:
49/84 + 168/84 = 49 + 168/84 = 217/84
217/84 simplified gives 31/12
So, 7/12 + 42/21 = 31/12
In mixed form: 27/12

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