Subtract 21/25 from 15/18
15/18 - 21/25 is -1/150.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 18 and 25 is 450
Next, find the equivalent fraction of both fractional numbers with denominator 450 - For the 1st fraction, since 18 × 25 = 450,
15/18 = 15 × 25/18 × 25 = 375/450 - Likewise, for the 2nd fraction, since 25 × 18 = 450,
21/25 = 21 × 18/25 × 18 = 378/450 - Subtract the two like fractions:
375/450 - 378/450 = 375 - 378/450 = -3/450 - After reducing the fraction, the answer is -1/150
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