Add 28/8 and 1/21, Solve 3 4/8 + 1/21 as a fraction

Add 28/8 and 1/21

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

28/8 + 1/21 is 149/42.

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,
28/8 = 28 × 21/8 × 21 = 588/168
Likewise, for the 2nd fraction, since 21 × 8 = 168,
1/21 = 1 × 8/21 × 8 = 8/168
Add the two like fractions:
588/168 + 8/168 = 588 + 8/168 = 596/168
596/168 simplified gives 149/42
So, 28/8 + 1/21 = 149/42
In mixed form: 323/42

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