Subtract 12/10 from 7/42, Solve 7/42

Subtract 12/10 from 7/42

1^st number: 7/42, 2^nd number: 1 2/10

7/42 - 12/10 is -31/30.

Find the least common denominator or LCM of the two denominators:
LCM of 42 and 10 is 210

Next, find the equivalent fraction of both fractional numbers with denominator 210
For the 1st fraction, since 42 × 5 = 210,
7/42 = 7 × 5/42 × 5 = 35/210
Likewise, for the 2nd fraction, since 10 × 21 = 210,
12/10 = 12 × 21/10 × 21 = 252/210
Subtract the two like fractions:
35/210 - 252/210 = 35 - 252/210 = -217/210
After reducing the fraction, the answer is -31/30

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