Subtract 30/21 from 3/90
1st number: 3/90, 2nd number: 1 9/21
3/90 - 30/21 is -293/210.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 90 and 21 is 630
Next, find the equivalent fraction of both fractional numbers with denominator 630 - For the 1st fraction, since 90 × 7 = 630,
3/90 = 3 × 7/90 × 7 = 21/630 - Likewise, for the 2nd fraction, since 21 × 30 = 630,
30/21 = 30 × 30/21 × 30 = 900/630 - Subtract the two like fractions:
21/630 - 900/630 = 21 - 900/630 = -879/630 - After reducing the fraction, the answer is -293/210
MathStep (Works offline)
Download our mobile app and learn to work with fractions in your own time:
Android and iPhone/ iPad
Related: 6/90-30/21 3/90-60/21 3/90-30/42 9/90-30/21 3/90-90/21 3/90-30/63 15/90-30/21 21/90-30/21