Subtract 90/84 from 5/15, Solve 5/15

Subtract 90/84 from 5/15

1^st number: 5/15, 2^nd number: 1 6/84

5/15 - 90/84 is -31/42.

Find the least common denominator or LCM of the two denominators:
LCM of 15 and 84 is 420

Next, find the equivalent fraction of both fractional numbers with denominator 420
For the 1st fraction, since 15 × 28 = 420,
5/15 = 5 × 28/15 × 28 = 140/420
Likewise, for the 2nd fraction, since 84 × 5 = 420,
90/84 = 90 × 5/84 × 5 = 450/420
Subtract the two like fractions:
140/420 - 450/420 = 140 - 450/420 = -310/420
After reducing the fraction, the answer is -31/42

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