Subtract 21/9 from 15/25, Solve 15/25

Subtract 21/9 from 15/25

1^st number: 15/25, 2^nd number: 2 3/9

15/25 - 21/9 is -26/15.

Find the least common denominator or LCM of the two denominators:
LCM of 25 and 9 is 225

Next, find the equivalent fraction of both fractional numbers with denominator 225
For the 1st fraction, since 25 × 9 = 225,
15/25 = 15 × 9/25 × 9 = 135/225
Likewise, for the 2nd fraction, since 9 × 25 = 225,
21/9 = 21 × 25/9 × 25 = 525/225
Subtract the two like fractions:
135/225 - 525/225 = 135 - 525/225 = -390/225
After reducing the fraction, the answer is -26/15

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