Subtract 80/21 from 15/8
1st number: 1 7/8, 2nd number: 3 17/21
15/8 - 80/21 is -325/168.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 8 and 21 is 168
Next, find the equivalent fraction of both fractional numbers with denominator 168 - For the 1st fraction, since 8 × 21 = 168,
15/8 = 15 × 21/8 × 21 = 315/168 - Likewise, for the 2nd fraction, since 21 × 8 = 168,
80/21 = 80 × 8/21 × 8 = 640/168 - Subtract the two like fractions:
315/168 - 640/168 = 315 - 640/168 = -325/168
MathStep (Works offline)
Download our mobile app and learn to work with fractions in your own time:
Android and iPhone/ iPad
Related: 30/8-80/21 15/16-80/21 15/8-80/42 45/8-80/21 15/24-80/21 15/8-80/63 75/8-80/21 15/40-80/21 15/56-80/21