Subtract 20/42 from 10/84
10/84 - 20/42 is -5/14.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 84 and 42 is 84
Next, find the equivalent fraction of both fractional numbers with denominator 84 - For the 1st fraction, since 84 × 1 = 84,
10/84 = 10 × 1/84 × 1 = 10/84 - Likewise, for the 2nd fraction, since 42 × 2 = 84,
20/42 = 20 × 2/42 × 2 = 40/84 - Subtract the two like fractions:
10/84 - 40/84 = 10 - 40/84 = -30/84 - After reducing the fraction, the answer is -5/14
MathStep (Works offline)
Download our mobile app and learn to work with fractions in your own time:
Android and iPhone/ iPad
Related: 20/84-20/42 10/84-40/42 10/84-20/84 30/84-20/42 10/84-60/42 50/84-20/42 70/84-20/42