Subtract 90/80 from 4/21
1st number: 4/21, 2nd number: 1 10/80
4/21 - 90/80 is -157/168.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 21 and 80 is 1680
Next, find the equivalent fraction of both fractional numbers with denominator 1680 - For the 1st fraction, since 21 × 80 = 1680,
4/21 = 4 × 80/21 × 80 = 320/1680 - Likewise, for the 2nd fraction, since 80 × 21 = 1680,
90/80 = 90 × 21/80 × 21 = 1890/1680 - Subtract the two like fractions:
320/1680 - 1890/1680 = 320 - 1890/1680 = -1570/1680 - After reducing the fraction, the answer is -157/168
MathStep (Works offline)
Download our mobile app and learn to work with fractions in your own time:
Android and iPhone/ iPad
Related: 8/21-90/80 4/42-90/80 12/21-90/80 4/63-90/80 20/21-90/80 28/21-90/80