Subtract 5/50 from 21/42, Solve 21/42

Subtract 5/50 from 21/42

21/42 - 5/50 is 2/5.

Find the least common denominator or LCM of the two denominators:
LCM of 42 and 50 is 1050

Next, find the equivalent fraction of both fractional numbers with denominator 1050
For the 1st fraction, since 42 × 25 = 1050,
21/42 = 21 × 25/42 × 25 = 525/1050
Likewise, for the 2nd fraction, since 50 × 21 = 1050,
5/50 = 5 × 21/50 × 21 = 105/1050
Subtract the two like fractions:
525/1050 - 105/1050 = 525 - 105/1050 = 420/1050
After reducing the fraction, the answer is 2/5

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