Subtract 84/81 from 40/84
1st number: 40/84, 2nd number: 1 3/81
40/84 - 84/81 is -106/189.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 84 and 81 is 2268
Next, find the equivalent fraction of both fractional numbers with denominator 2268 - For the 1st fraction, since 84 × 27 = 2268,
40/84 = 40 × 27/84 × 27 = 1080/2268 - Likewise, for the 2nd fraction, since 81 × 28 = 2268,
84/81 = 84 × 28/81 × 28 = 2352/2268 - Subtract the two like fractions:
1080/2268 - 2352/2268 = 1080 - 2352/2268 = -1272/2268 - After reducing the fraction, the answer is -106/189
MathStep (Works offline)
Download our mobile app and learn to work with fractions in your own time:
Android and iPhone/ iPad
Related: 80/84-84/81