Subtract 90/20 from 9/7
1st number: 1 2/7, 2nd number: 4 10/20
9/7 - 90/20 is -45/14.
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,
9/7 = 9 × 20/7 × 20 = 180/140 - Likewise, for the 2nd fraction, since 20 × 7 = 140,
90/20 = 90 × 7/20 × 7 = 630/140 - Subtract the two like fractions:
180/140 - 630/140 = 180 - 630/140 = -450/140 - After reducing the fraction, the answer is -45/14
MathStep (Works offline)
Download our mobile app and learn to work with fractions in your own time:
Android and iPhone/ iPad
Related: 18/7-90/20 9/14-90/20 9/7-90/40 27/7-90/20 9/21-90/20 9/7-90/60 45/7-90/20 9/35-90/20 63/7-90/20 9/49-90/20