Subtract 20/80 from 5/42
5/42 - 20/80 is -11/84.
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,
5/42 = 5 × 40/42 × 40 = 200/1680 - Likewise, for the 2nd fraction, since 80 × 21 = 1680,
20/80 = 20 × 21/80 × 21 = 420/1680 - Subtract the two like fractions:
200/1680 - 420/1680 = 200 - 420/1680 = -220/1680 - After reducing the fraction, the answer is -11/84
MathStep (Works offline)
Download our mobile app and learn to work with fractions in your own time:
Android and iPhone/ iPad
Related: 10/42-20/80 5/42-40/80 5/84-20/80 15/42-20/80 5/42-60/80 25/42-20/80 35/42-20/80