Subtract 4/20 from 7/90
7/90 - 4/20 is -11/90.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 90 and 20 is 180
Next, find the equivalent fraction of both fractional numbers with denominator 180 - For the 1st fraction, since 90 × 2 = 180,
7/90 = 7 × 2/90 × 2 = 14/180 - Likewise, for the 2nd fraction, since 20 × 9 = 180,
4/20 = 4 × 9/20 × 9 = 36/180 - Subtract the two like fractions:
14/180 - 36/180 = 14 - 36/180 = -22/180 - After reducing the fraction, the answer is -11/90
MathStep (Works offline)
Download our mobile app and learn to work with fractions in your own time:
Android and iPhone/ iPad
Related: 14/90-4/20 7/90-8/20 7/90-4/40 21/90-4/20 7/90-12/20 7/90-4/60 35/90-4/20 49/90-4/20 7/90-28/20