Subtract 28/8 from 72/84, Solve 72/84

Subtract 28/8 from 72/84

1^st number: 72/84, 2^nd number: 3 4/8

72/84 - 28/8 is -37/14.

Find the least common denominator or LCM of the two denominators:
LCM of 84 and 8 is 168

Next, find the equivalent fraction of both fractional numbers with denominator 168
For the 1st fraction, since 84 × 2 = 168,
72/84 = 72 × 2/84 × 2 = 144/168
Likewise, for the 2nd fraction, since 8 × 21 = 168,
28/8 = 28 × 21/8 × 21 = 588/168
Subtract the two like fractions:
144/168 - 588/168 = 144 - 588/168 = -444/168
After reducing the fraction, the answer is -37/14

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