Subtract 8/80 from 20/42
20/42 - 8/80 is 79/210.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 42 and 80 is 1680
Next, find the equivalent fraction of both fractional numbers with denominator 1680 - For the 1st fraction, since 42 × 40 = 1680,
20/42 = 20 × 40/42 × 40 = 800/1680 - Likewise, for the 2nd fraction, since 80 × 21 = 1680,
8/80 = 8 × 21/80 × 21 = 168/1680 - Subtract the two like fractions:
800/1680 - 168/1680 = 800 - 168/1680 = 632/1680 - After reducing the fraction, the answer is 79/210
MathStep (Works offline)
Download our mobile app and learn to work with fractions in your own time:
Android and iPhone/ iPad
Related: 40/42-8/80 20/42-16/80 20/84-8/80 60/42-8/80 20/42-24/80 20/42-40/80 20/42-56/80