Add 28/8 and 42/21, Solve 3 4/8 + 2 0/21 as a fraction

Add 28/8 and 42/21

1^st number: 3 4/8, 2^nd number: 2 0/21

28/8 + 42/21 is 11/2.

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,
42/21 = 42 × 8/21 × 8 = 336/168
Add the two like fractions:
588/168 + 336/168 = 588 + 336/168 = 924/168
924/168 simplified gives 11/2
So, 28/8 + 42/21 = 11/2
In mixed form: 51/2

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