Subtract 90/18 from 5/7
1st number: 5/7, 2nd number: 5 0/18
5/7 - 90/18 is -30/7.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 7 and 18 is 126
Next, find the equivalent fraction of both fractional numbers with denominator 126 - For the 1st fraction, since 7 × 18 = 126,
5/7 = 5 × 18/7 × 18 = 90/126 - Likewise, for the 2nd fraction, since 18 × 7 = 126,
90/18 = 90 × 7/18 × 7 = 630/126 - Subtract the two like fractions:
90/126 - 630/126 = 90 - 630/126 = -540/126 - After reducing the fraction, the answer is -30/7
MathStep (Works offline)
Download our mobile app and learn to work with fractions in your own time:
Android and iPhone/ iPad
Related: 10/7-90/18 5/14-90/18 5/7-90/36 15/7-90/18 5/21-90/18 5/7-90/54 25/7-90/18 5/35-90/18 35/7-90/18 5/49-90/18