Subtract 20/42 from 5/30, Solve 5/30

Subtract 20/42 from 5/30

5/30 - 20/42 is -13/42.

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

Next, find the equivalent fraction of both fractional numbers with denominator 210
For the 1st fraction, since 30 × 7 = 210,
5/30 = 5 × 7/30 × 7 = 35/210
Likewise, for the 2nd fraction, since 42 × 5 = 210,
20/42 = 20 × 5/42 × 5 = 100/210
Subtract the two like fractions:
35/210 - 100/210 = 35 - 100/210 = -65/210
After reducing the fraction, the answer is -13/42

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