Subtract 4/25 from 21/45, Solve 21/45

Subtract 4/25 from 21/45

21/45 - 4/25 is 23/75.

Find the least common denominator or LCM of the two denominators:
LCM of 45 and 25 is 225

Next, find the equivalent fraction of both fractional numbers with denominator 225
For the 1st fraction, since 45 × 5 = 225,
21/45 = 21 × 5/45 × 5 = 105/225
Likewise, for the 2nd fraction, since 25 × 9 = 225,
4/25 = 4 × 9/25 × 9 = 36/225
Subtract the two like fractions:
105/225 - 36/225 = 105 - 36/225 = 69/225
After reducing the fraction, the answer is 23/75

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