Subtract 18/15 from 12/28
1st number: 12/28, 2nd number: 1 3/15
12/28 - 18/15 is -27/35.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 28 and 15 is 420
Next, find the equivalent fraction of both fractional numbers with denominator 420 - For the 1st fraction, since 28 × 15 = 420,
12/28 = 12 × 15/28 × 15 = 180/420 - Likewise, for the 2nd fraction, since 15 × 28 = 420,
18/15 = 18 × 28/15 × 28 = 504/420 - Subtract the two like fractions:
180/420 - 504/420 = 180 - 504/420 = -324/420 - After reducing the fraction, the answer is -27/35
MathStep (Works offline)
Download our mobile app and learn to work with fractions in your own time:
Android and iPhone/ iPad
Related: 24/28-18/15 12/28-36/15 12/56-18/15 12/28-18/30 36/28-18/15 12/28-54/15 12/84-18/15 12/28-18/45 60/28-18/15 12/28-90/15 12/28-18/75 84/28-18/15