Subtract 18/81 from 1/30
1/30 - 18/81 is -17/90.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 30 and 81 is 810
Next, find the equivalent fraction of both fractional numbers with denominator 810 - For the 1st fraction, since 30 × 27 = 810,
1/30 = 1 × 27/30 × 27 = 27/810 - Likewise, for the 2nd fraction, since 81 × 10 = 810,
18/81 = 18 × 10/81 × 10 = 180/810 - Subtract the two like fractions:
27/810 - 180/810 = 27 - 180/810 = -153/810 - After reducing the fraction, the answer is -17/90
MathStep (Works offline)
Download our mobile app and learn to work with fractions in your own time:
Android and iPhone/ iPad
Related: 2/30-18/81 1/30-36/81 1/60-18/81 3/30-18/81 1/30-54/81 1/90-18/81 5/30-18/81 1/30-90/81 7/30-18/81