Subtract 42/9 from 80/81
1st number: 80/81, 2nd number: 4 6/9
80/81 - 42/9 is -298/81.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 81 and 9 is 81
Next, find the equivalent fraction of both fractional numbers with denominator 81 - For the 1st fraction, since 81 × 1 = 81,
80/81 = 80 × 1/81 × 1 = 80/81 - Likewise, for the 2nd fraction, since 9 × 9 = 81,
42/9 = 42 × 9/9 × 9 = 378/81 - Subtract the two like fractions:
80/81 - 378/81 = 80 - 378/81 = -298/81
MathStep (Works offline)
Download our mobile app and learn to work with fractions in your own time:
Android and iPhone/ iPad
Related: 80/81-84/9 80/81-42/18 80/81-42/27 80/81-42/45 80/81-42/63