Subtract 42/30 from 4/42, Solve 4/42

Subtract 42/30 from 4/42

1^st number: 4/42, 2^nd number: 1 12/30

4/42 - 42/30 is -137/105.

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,
4/42 = 4 × 5/42 × 5 = 20/210
Likewise, for the 2nd fraction, since 30 × 7 = 210,
42/30 = 42 × 7/30 × 7 = 294/210
Subtract the two like fractions:
20/210 - 294/210 = 20 - 294/210 = -274/210
After reducing the fraction, the answer is -137/105

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