Subtract 49/40 from 20/90
1st number: 20/90, 2nd number: 1 9/40
20/90 - 49/40 is -361/360.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 90 and 40 is 360
Next, find the equivalent fraction of both fractional numbers with denominator 360 - For the 1st fraction, since 90 × 4 = 360,
20/90 = 20 × 4/90 × 4 = 80/360 - Likewise, for the 2nd fraction, since 40 × 9 = 360,
49/40 = 49 × 9/40 × 9 = 441/360 - Subtract the two like fractions:
80/360 - 441/360 = 80 - 441/360 = -361/360
MathStep (Works offline)
Download our mobile app and learn to work with fractions in your own time:
Android and iPhone/ iPad
Related: 40/90-49/40 20/90-98/40 20/90-49/80 60/90-49/40