Subtract 80/42 from 5/15, Solve 5/15

Subtract 80/42 from 5/15

1^st number: 5/15, 2^nd number: 1 38/42

5/15 - 80/42 is -11/7.

Find the least common denominator or LCM of the two denominators:
LCM of 15 and 42 is 210

Next, find the equivalent fraction of both fractional numbers with denominator 210
For the 1st fraction, since 15 × 14 = 210,
5/15 = 5 × 14/15 × 14 = 70/210
Likewise, for the 2nd fraction, since 42 × 5 = 210,
80/42 = 80 × 5/42 × 5 = 400/210
Subtract the two like fractions:
70/210 - 400/210 = 70 - 400/210 = -330/210
After reducing the fraction, the answer is -11/7

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