Subtract 28/80 from 15/84, Solve 15/84

Subtract 28/80 from 15/84

15/84 - 28/80 is -6/35.

Find the least common denominator or LCM of the two denominators:
LCM of 84 and 80 is 1680

Next, find the equivalent fraction of both fractional numbers with denominator 1680
For the 1st fraction, since 84 × 20 = 1680,
15/84 = 15 × 20/84 × 20 = 300/1680
Likewise, for the 2nd fraction, since 80 × 21 = 1680,
28/80 = 28 × 21/80 × 21 = 588/1680
Subtract the two like fractions:
300/1680 - 588/1680 = 300 - 588/1680 = -288/1680
After reducing the fraction, the answer is -6/35

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