Subtract 18/50 from 1/21, Solve 1/21

Subtract 18/50 from 1/21

1/21 - 18/50 is -164/525.

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,
1/21 = 1 × 50/21 × 50 = 50/1050
Likewise, for the 2nd fraction, since 50 × 21 = 1050,
18/50 = 18 × 21/50 × 21 = 378/1050
Subtract the two like fractions:
50/1050 - 378/1050 = 50 - 378/1050 = -328/1050
After reducing the fraction, the answer is -164/525

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