Subtract 9/25 from 18/21, Solve 18/21

Subtract 9/25 from 18/21

18/21 - 9/25 is 87/175.

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,
18/21 = 18 × 25/21 × 25 = 450/525
Likewise, for the 2nd fraction, since 25 × 21 = 525,
9/25 = 9 × 21/25 × 21 = 189/525
Subtract the two like fractions:
450/525 - 189/525 = 450 - 189/525 = 261/525
After reducing the fraction, the answer is 87/175

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