Subtract 15/81 from 20/84
20/84 - 15/81 is 10/189.
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,
20/84 = 20 × 27/84 × 27 = 540/2268 - Likewise, for the 2nd fraction, since 81 × 28 = 2268,
15/81 = 15 × 28/81 × 28 = 420/2268 - Subtract the two like fractions:
540/2268 - 420/2268 = 540 - 420/2268 = 120/2268 - After reducing the fraction, the answer is 10/189
MathStep (Works offline)
Download our mobile app and learn to work with fractions in your own time:
Android and iPhone/ iPad
Related: 40/84-15/81 20/84-30/81 60/84-15/81 20/84-45/81 20/84-75/81