Subtract 42/15 from 30/42, Solve 30/42

Subtract 42/15 from 30/42

1^st number: 30/42, 2^nd number: 2 12/15

30/42 - 42/15 is -73/35.

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

Next, find the equivalent fraction of both fractional numbers with denominator 210
For the 1st fraction, since 42 × 5 = 210,
30/42 = 30 × 5/42 × 5 = 150/210
Likewise, for the 2nd fraction, since 15 × 14 = 210,
42/15 = 42 × 14/15 × 14 = 588/210
Subtract the two like fractions:
150/210 - 588/210 = 150 - 588/210 = -438/210
After reducing the fraction, the answer is -73/35

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