Subtract 21/90 from 20/5
1st number: 4 0/5, 2nd number: 21/90
20/5 - 21/90 is 113/30.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 5 and 90 is 90
Next, find the equivalent fraction of both fractional numbers with denominator 90 - For the 1st fraction, since 5 × 18 = 90,
20/5 = 20 × 18/5 × 18 = 360/90 - Likewise, for the 2nd fraction, since 90 × 1 = 90,
21/90 = 21 × 1/90 × 1 = 21/90 - Subtract the two like fractions:
360/90 - 21/90 = 360 - 21/90 = 339/90 - After reducing the fraction, the answer is 113/30
- In mixed form: 323/30
MathStep (Works offline)
Download our mobile app and learn to work with fractions in your own time:
Android and iPhone/ iPad
Related: 40/5-21/90 20/5-42/90 20/10-21/90 60/5-21/90 20/5-63/90 20/15-21/90 20/25-21/90 20/35-21/90