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

Subtract 5/42 from 4/20

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

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

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

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