Subtract 20/45 from 27/90
27/90 - 20/45 is -13/90.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 90 and 45 is 90
Next, find the equivalent fraction of both fractional numbers with denominator 90 - For the 1st fraction, since 90 × 1 = 90,
27/90 = 27 × 1/90 × 1 = 27/90 - Likewise, for the 2nd fraction, since 45 × 2 = 90,
20/45 = 20 × 2/45 × 2 = 40/90 - Subtract the two like fractions:
27/90 - 40/90 = 27 - 40/90 = -13/90
MathStep (Works offline)
Download our mobile app and learn to work with fractions in your own time:
Android and iPhone/ iPad
Related: 54/90-20/45 27/90-40/45 27/90-20/90 81/90-20/45 27/90-60/45