Subtract 9/42 from 4/81
4/81 - 9/42 is -187/1134.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 81 and 42 is 1134
Next, find the equivalent fraction of both fractional numbers with denominator 1134 - For the 1st fraction, since 81 × 14 = 1134,
4/81 = 4 × 14/81 × 14 = 56/1134 - Likewise, for the 2nd fraction, since 42 × 27 = 1134,
9/42 = 9 × 27/42 × 27 = 243/1134 - Subtract the two like fractions:
56/1134 - 243/1134 = 56 - 243/1134 = -187/1134
MathStep (Works offline)
Download our mobile app and learn to work with fractions in your own time:
Android and iPhone/ iPad
Related: 8/81-9/42 4/81-18/42 4/81-9/84 12/81-9/42 4/81-27/42 20/81-9/42 4/81-45/42 28/81-9/42 4/81-63/42