Subtract 10/25 from 8/21, Solve 8/21

Subtract 10/25 from 8/21

8/21 - 10/25 is -2/105.

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,
8/21 = 8 × 25/21 × 25 = 200/525
Likewise, for the 2nd fraction, since 25 × 21 = 525,
10/25 = 10 × 21/25 × 21 = 210/525
Subtract the two like fractions:
200/525 - 210/525 = 200 - 210/525 = -10/525
After reducing the fraction, the answer is -2/105

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