Subtract 30/70 from 7/42, Solve 7/42

Subtract 30/70 from 7/42

7/42 - 30/70 is -11/42.

Find the least common denominator or LCM of the two denominators:
LCM of 42 and 70 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 70 × 3 = 210,
30/70 = 30 × 3/70 × 3 = 90/210
Subtract the two like fractions:
35/210 - 90/210 = 35 - 90/210 = -55/210
After reducing the fraction, the answer is -11/42

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