Subtract 42/15 from 40/42, Solve 40/42

Subtract 42/15 from 40/42

1^st number: 40/42, 2^nd number: 2 12/15

40/42 - 42/15 is -194/105.

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,
40/42 = 40 × 5/42 × 5 = 200/210
Likewise, for the 2nd fraction, since 15 × 14 = 210,
42/15 = 42 × 14/15 × 14 = 588/210
Subtract the two like fractions:
200/210 - 588/210 = 200 - 588/210 = -388/210
After reducing the fraction, the answer is -194/105

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