Subtract 3/7 from 18/90
18/90 - 3/7 is -8/35.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 90 and 7 is 630
Next, find the equivalent fraction of both fractional numbers with denominator 630 - For the 1st fraction, since 90 × 7 = 630,
18/90 = 18 × 7/90 × 7 = 126/630 - Likewise, for the 2nd fraction, since 7 × 90 = 630,
3/7 = 3 × 90/7 × 90 = 270/630 - Subtract the two like fractions:
126/630 - 270/630 = 126 - 270/630 = -144/630 - After reducing the fraction, the answer is -8/35
MathStep (Works offline)
Download our mobile app and learn to work with fractions in your own time:
Android and iPhone/ iPad
Related: 36/90-3/7 18/90-6/7 18/90-3/14 54/90-3/7 18/90-9/7 18/90-3/21 18/90-15/7 18/90-3/35 18/90-21/7 18/90-3/49