Subtract 28/25 from 18/21
1st number: 18/21, 2nd number: 1 3/25
18/21 - 28/25 is -46/175.
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,
28/25 = 28 × 21/25 × 21 = 588/525 - Subtract the two like fractions:
450/525 - 588/525 = 450 - 588/525 = -138/525 - After reducing the fraction, the answer is -46/175
MathStep (Works offline)
Download our mobile app and learn to work with fractions in your own time:
Android and iPhone/ iPad
Related: 36/21-28/25 18/21-56/25 18/42-28/25 18/21-28/50 54/21-28/25 18/21-84/25 18/63-28/25 18/21-28/75 90/21-28/25