Subtract 81/42 from 2/84
1st number: 2/84, 2nd number: 1 39/42
2/84 - 81/42 is -40/21.
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,
2/84 = 2 × 1/84 × 1 = 2/84 - Likewise, for the 2nd fraction, since 42 × 2 = 84,
81/42 = 81 × 2/42 × 2 = 162/84 - Subtract the two like fractions:
2/84 - 162/84 = 2 - 162/84 = -160/84 - After reducing the fraction, the answer is -40/21
MathStep (Works offline)
Download our mobile app and learn to work with fractions in your own time:
Android and iPhone/ iPad
Related: 4/84-81/42 2/84-81/84 6/84-81/42 10/84-81/42 14/84-81/42