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

Subtract 21/9 from 18/25

1^st number: 18/25, 2^nd number: 2 3/9

18/25 - 21/9 is -121/75.

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,
18/25 = 18 × 9/25 × 9 = 162/225
Likewise, for the 2nd fraction, since 9 × 25 = 225,
21/9 = 21 × 25/9 × 25 = 525/225
Subtract the two like fractions:
162/225 - 525/225 = 162 - 525/225 = -363/225
After reducing the fraction, the answer is -121/75

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