Subtract 36/30 from 15/42, Solve 15/42

Subtract 36/30 from 15/42

1^st number: 15/42, 2^nd number: 1 6/30

15/42 - 36/30 is -59/70.

Find the least common denominator or LCM of the two denominators:
LCM of 42 and 30 is 210

Next, find the equivalent fraction of both fractional numbers with denominator 210
For the 1st fraction, since 42 × 5 = 210,
15/42 = 15 × 5/42 × 5 = 75/210
Likewise, for the 2nd fraction, since 30 × 7 = 210,
36/30 = 36 × 7/30 × 7 = 252/210
Subtract the two like fractions:
75/210 - 252/210 = 75 - 252/210 = -177/210
After reducing the fraction, the answer is -59/70

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