Subtract 80/10 from 90/21
1st number: 4 6/21, 2nd number: 8 0/10
90/21 - 80/10 is -26/7.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 21 and 10 is 210
Next, find the equivalent fraction of both fractional numbers with denominator 210 - For the 1st fraction, since 21 × 10 = 210,
90/21 = 90 × 10/21 × 10 = 900/210 - Likewise, for the 2nd fraction, since 10 × 21 = 210,
80/10 = 80 × 21/10 × 21 = 1680/210 - Subtract the two like fractions:
900/210 - 1680/210 = 900 - 1680/210 = -780/210 - After reducing the fraction, the answer is -26/7
MathStep (Works offline)
Download our mobile app and learn to work with fractions in your own time:
Android and iPhone/ iPad
Related: 90/42-80/10 90/21-80/20 90/63-80/10 90/21-80/30 90/21-80/50 90/21-80/70