Subtract 21/20 from 90/30
1st number: 3 0/30, 2nd number: 1 1/20
90/30 - 21/20 is 39/20.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 30 and 20 is 60
Next, find the equivalent fraction of both fractional numbers with denominator 60 - For the 1st fraction, since 30 × 2 = 60,
90/30 = 90 × 2/30 × 2 = 180/60 - Likewise, for the 2nd fraction, since 20 × 3 = 60,
21/20 = 21 × 3/20 × 3 = 63/60 - Subtract the two like fractions:
180/60 - 63/60 = 180 - 63/60 = 117/60 - After reducing the fraction, the answer is 39/20
- In mixed form: 119/20
MathStep (Works offline)
Download our mobile app and learn to work with fractions in your own time:
Android and iPhone/ iPad
Related: 90/30-42/20 90/60-21/20 90/30-21/40 90/30-63/20 90/30-21/60