Subtract 10/25 from 5/21, Solve 5/21

Subtract 10/25 from 5/21

5/21 - 10/25 is -17/105.

Find the least common denominator or LCM of the two denominators:
LCM of 21 and 25 is 525

Next, find the equivalent fraction of both fractional numbers with denominator 525
For the 1st fraction, since 21 × 25 = 525,
5/21 = 5 × 25/21 × 25 = 125/525
Likewise, for the 2nd fraction, since 25 × 21 = 525,
10/25 = 10 × 21/25 × 21 = 210/525
Subtract the two like fractions:
125/525 - 210/525 = 125 - 210/525 = -85/525
After reducing the fraction, the answer is -17/105

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