Add 12/8 and 72/21, Solve 1 4/8 + 3 9/21 as a fraction

Add 12/8 and 72/21

1^st number: 1 4/8, 2^nd number: 3 9/21

12/8 + 72/21 is 69/14.

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

Next, find the equivalent fraction of both fractional numbers with denominator 168
For the 1st fraction, since 8 × 21 = 168,
12/8 = 12 × 21/8 × 21 = 252/168
Likewise, for the 2nd fraction, since 21 × 8 = 168,
72/21 = 72 × 8/21 × 8 = 576/168
Add the two like fractions:
252/168 + 576/168 = 252 + 576/168 = 828/168
828/168 simplified gives 69/14
So, 12/8 + 72/21 = 69/14
In mixed form: 413/14

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