Subtract 9/72 from 21/25, Solve 21/25

Subtract 9/72 from 21/25

21/25 - 9/72 is 143/200.

Find the least common denominator or LCM of the two denominators:
LCM of 25 and 72 is 1800

Next, find the equivalent fraction of both fractional numbers with denominator 1800
For the 1st fraction, since 25 × 72 = 1800,
21/25 = 21 × 72/25 × 72 = 1512/1800
Likewise, for the 2nd fraction, since 72 × 25 = 1800,
9/72 = 9 × 25/72 × 25 = 225/1800
Subtract the two like fractions:
1512/1800 - 225/1800 = 1512 - 225/1800 = 1287/1800
After reducing the fraction, the answer is 143/200

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