Add 12/21 and 45/16, Solve 12/21 + 2 13/16 as a fraction

Add 12/21 and 45/16

1^st number: 12/21, 2^nd number: 2 13/16

12/21 + 45/16 is 379/112.

Find the least common denominator or LCM of the two denominators:
LCM of 21 and 16 is 336

Next, find the equivalent fraction of both fractional numbers with denominator 336
For the 1st fraction, since 21 × 16 = 336,
12/21 = 12 × 16/21 × 16 = 192/336
Likewise, for the 2nd fraction, since 16 × 21 = 336,
45/16 = 45 × 21/16 × 21 = 945/336
Add the two like fractions:
192/336 + 945/336 = 192 + 945/336 = 1137/336
1137/336 simplified gives 379/112
So, 12/21 + 45/16 = 379/112
In mixed form: 343/112

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