Subtract 45/42 from 12/70, Solve 12/70

Subtract 45/42 from 12/70

1^st number: 12/70, 2^nd number: 1 3/42

12/70 - 45/42 is -9/10.

Find the least common denominator or LCM of the two denominators:
LCM of 70 and 42 is 210

Next, find the equivalent fraction of both fractional numbers with denominator 210
For the 1st fraction, since 70 × 3 = 210,
12/70 = 12 × 3/70 × 3 = 36/210
Likewise, for the 2nd fraction, since 42 × 5 = 210,
45/42 = 45 × 5/42 × 5 = 225/210
Subtract the two like fractions:
36/210 - 225/210 = 36 - 225/210 = -189/210
After reducing the fraction, the answer is -9/10

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