Subtract 70/49 from 28/84, Solve 28/84

Subtract 70/49 from 28/84

1^st number: 28/84, 2^nd number: 1 21/49

28/84 - 70/49 is -23/21.

Find the least common denominator or LCM of the two denominators:
LCM of 84 and 49 is 588

Next, find the equivalent fraction of both fractional numbers with denominator 588
For the 1st fraction, since 84 × 7 = 588,
28/84 = 28 × 7/84 × 7 = 196/588
Likewise, for the 2nd fraction, since 49 × 12 = 588,
70/49 = 70 × 12/49 × 12 = 840/588
Subtract the two like fractions:
196/588 - 840/588 = 196 - 840/588 = -644/588
After reducing the fraction, the answer is -23/21

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