Add 12/21 and 27/8, Solve 12/21 + 3 3/8 as a fraction

Add 12/21 and 27/8

1^st number: 12/21, 2^nd number: 3 3/8

12/21 + 27/8 is 221/56.

Find the least common denominator or LCM of the two denominators:
LCM of 21 and 8 is 168

Next, find the equivalent fraction of both fractional numbers with denominator 168
For the 1st fraction, since 21 × 8 = 168,
12/21 = 12 × 8/21 × 8 = 96/168
Likewise, for the 2nd fraction, since 8 × 21 = 168,
27/8 = 27 × 21/8 × 21 = 567/168
Add the two like fractions:
96/168 + 567/168 = 96 + 567/168 = 663/168
663/168 simplified gives 221/56
So, 12/21 + 27/8 = 221/56
In mixed form: 353/56

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