Subtract 18/25 from 4/21
4/21 - 18/25 is -278/525.
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,
4/21 = 4 × 25/21 × 25 = 100/525 - Likewise, for the 2nd fraction, since 25 × 21 = 525,
18/25 = 18 × 21/25 × 21 = 378/525 - Subtract the two like fractions:
100/525 - 378/525 = 100 - 378/525 = -278/525
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