Subtract 10/42 from 18/84
18/84 - 10/42 is -1/42.
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,
18/84 = 18 × 1/84 × 1 = 18/84 - Likewise, for the 2nd fraction, since 42 × 2 = 84,
10/42 = 10 × 2/42 × 2 = 20/84 - Subtract the two like fractions:
18/84 - 20/84 = 18 - 20/84 = -2/84 - After reducing the fraction, the answer is -1/42
MathStep (Works offline)
Download our mobile app and learn to work with fractions in your own time:
Android and iPhone/ iPad
Related: 36/84-10/42 18/84-20/42 18/84-10/84 54/84-10/42 18/84-30/42 90/84-10/42 18/84-50/42 18/84-70/42