Subtract 15/25 from 18/21
18/21 - 15/25 is 9/35.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 21 and 25 is 525
Next, find the equivalent fraction of both fractional numbers with denominator 525 - For the 1st fraction, since 21 × 25 = 525,
18/21 = 18 × 25/21 × 25 = 450/525 - Likewise, for the 2nd fraction, since 25 × 21 = 525,
15/25 = 15 × 21/25 × 21 = 315/525 - Subtract the two like fractions:
450/525 - 315/525 = 450 - 315/525 = 135/525 - After reducing the fraction, the answer is 9/35
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