Subtract 72/20 from 90/7
1st number: 12 6/7, 2nd number: 3 12/20
90/7 - 72/20 is 324/35.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 7 and 20 is 140
Next, find the equivalent fraction of both fractional numbers with denominator 140 - For the 1st fraction, since 7 × 20 = 140,
90/7 = 90 × 20/7 × 20 = 1800/140 - Likewise, for the 2nd fraction, since 20 × 7 = 140,
72/20 = 72 × 7/20 × 7 = 504/140 - Subtract the two like fractions:
1800/140 - 504/140 = 1800 - 504/140 = 1296/140 - After reducing the fraction, the answer is 324/35
- In mixed form: 99/35
MathStep (Works offline)
Download our mobile app and learn to work with fractions in your own time:
Android and iPhone/ iPad
Related: 90/14-72/20 90/7-72/40 90/21-72/20 90/7-72/60 90/35-72/20 90/49-72/20