Subtract 2/20 from 20/42, Solve 20/42

Subtract 2/20 from 20/42

20/42 - 2/20 is 79/210.

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,
20/42 = 20 × 10/42 × 10 = 200/420
Likewise, for the 2nd fraction, since 20 × 21 = 420,
2/20 = 2 × 21/20 × 21 = 42/420
Subtract the two like fractions:
200/420 - 42/420 = 200 - 42/420 = 158/420
After reducing the fraction, the answer is 79/210

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