Subtract 4/20 from 5/42, Solve 5/42

Subtract 4/20 from 5/42

5/42 - 4/20 is -17/210.

Find the least common denominator or LCM of the two denominators:
LCM of 42 and 20 is 420

Next, find the equivalent fraction of both fractional numbers with denominator 420
For the 1st fraction, since 42 × 10 = 420,
5/42 = 5 × 10/42 × 10 = 50/420
Likewise, for the 2nd fraction, since 20 × 21 = 420,
4/20 = 4 × 21/20 × 21 = 84/420
Subtract the two like fractions:
50/420 - 84/420 = 50 - 84/420 = -34/420
After reducing the fraction, the answer is -17/210

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