Subtract 21/20 from 90/2
1st number: 45 0/2, 2nd number: 1 1/20
90/2 - 21/20 is 879/20.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 2 and 20 is 20
Next, find the equivalent fraction of both fractional numbers with denominator 20 - For the 1st fraction, since 2 × 10 = 20,
90/2 = 90 × 10/2 × 10 = 900/20 - Likewise, for the 2nd fraction, since 20 × 1 = 20,
21/20 = 21 × 1/20 × 1 = 21/20 - Subtract the two like fractions:
900/20 - 21/20 = 900 - 21/20 = 879/20 - In mixed form: 4319/20
MathStep (Works offline)
Download our mobile app and learn to work with fractions in your own time:
Android and iPhone/ iPad
Related: 90/2-42/20 90/4-21/20 90/2-21/40 90/2-63/20 90/6-21/20 90/2-21/60 90/10-21/20 90/14-21/20