Add 4/56 and 72/21, Solve 4/56 + 3 9/21 as a fraction

Add 4/56 and 72/21

1^st number: 4/56, 2^nd number: 3 9/21

4/56 + 72/21 is 7/2.

Find the least common denominator or LCM of the two denominators:
LCM of 56 and 21 is 168

Next, find the equivalent fraction of both fractional numbers with denominator 168
For the 1st fraction, since 56 × 3 = 168,
4/56 = 4 × 3/56 × 3 = 12/168
Likewise, for the 2nd fraction, since 21 × 8 = 168,
72/21 = 72 × 8/21 × 8 = 576/168
Add the two like fractions:
12/168 + 576/168 = 12 + 576/168 = 588/168
588/168 simplified gives 7/2
So, 4/56 + 72/21 = 7/2
In mixed form: 31/2

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