Subtract 42/50 from 18/21, Solve 18/21

Subtract 42/50 from 18/21

18/21 - 42/50 is 3/175.

Find the least common denominator or LCM of the two denominators:
LCM of 21 and 50 is 1050

Next, find the equivalent fraction of both fractional numbers with denominator 1050
For the 1st fraction, since 21 × 50 = 1050,
18/21 = 18 × 50/21 × 50 = 900/1050
Likewise, for the 2nd fraction, since 50 × 21 = 1050,
42/50 = 42 × 21/50 × 21 = 882/1050
Subtract the two like fractions:
900/1050 - 882/1050 = 900 - 882/1050 = 18/1050
After reducing the fraction, the answer is 3/175

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