Subtract 6/90 from 3/21
3/21 - 6/90 is 8/105.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 21 and 90 is 630
Next, find the equivalent fraction of both fractional numbers with denominator 630 - For the 1st fraction, since 21 × 30 = 630,
3/21 = 3 × 30/21 × 30 = 90/630 - Likewise, for the 2nd fraction, since 90 × 7 = 630,
6/90 = 6 × 7/90 × 7 = 42/630 - Subtract the two like fractions:
90/630 - 42/630 = 90 - 42/630 = 48/630 - After reducing the fraction, the answer is 8/105
MathStep (Works offline)
Download our mobile app and learn to work with fractions in your own time:
Android and iPhone/ iPad
Related: 6/21-6/90 3/21-12/90 3/42-6/90 9/21-6/90 3/21-18/90 3/63-6/90 15/21-6/90 3/21-30/90 3/21-42/90