Subtract 4/25 from 20/42, Solve 20/42

Subtract 4/25 from 20/42

20/42 - 4/25 is 166/525.

Find the least common denominator or LCM of the two denominators:
LCM of 42 and 25 is 1050

Next, find the equivalent fraction of both fractional numbers with denominator 1050
For the 1st fraction, since 42 × 25 = 1050,
20/42 = 20 × 25/42 × 25 = 500/1050
Likewise, for the 2nd fraction, since 25 × 42 = 1050,
4/25 = 4 × 42/25 × 42 = 168/1050
Subtract the two like fractions:
500/1050 - 168/1050 = 500 - 168/1050 = 332/1050
After reducing the fraction, the answer is 166/525

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