Subtract 20/50 from 4/90
4/90 - 20/50 is -16/45.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 90 and 50 is 450
Next, find the equivalent fraction of both fractional numbers with denominator 450 - For the 1st fraction, since 90 × 5 = 450,
4/90 = 4 × 5/90 × 5 = 20/450 - Likewise, for the 2nd fraction, since 50 × 9 = 450,
20/50 = 20 × 9/50 × 9 = 180/450 - Subtract the two like fractions:
20/450 - 180/450 = 20 - 180/450 = -160/450 - After reducing the fraction, the answer is -16/45
MathStep (Works offline)
Download our mobile app and learn to work with fractions in your own time:
Android and iPhone/ iPad
Related: 8/90-20/50 4/90-40/50 12/90-20/50 4/90-60/50 20/90-20/50 28/90-20/50