Subtract 28/81 from 4/20
4/20 - 28/81 is -59/405.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 20 and 81 is 1620
Next, find the equivalent fraction of both fractional numbers with denominator 1620 - For the 1st fraction, since 20 × 81 = 1620,
4/20 = 4 × 81/20 × 81 = 324/1620 - Likewise, for the 2nd fraction, since 81 × 20 = 1620,
28/81 = 28 × 20/81 × 20 = 560/1620 - Subtract the two like fractions:
324/1620 - 560/1620 = 324 - 560/1620 = -236/1620 - After reducing the fraction, the answer is -59/405
MathStep (Works offline)
Download our mobile app and learn to work with fractions in your own time:
Android and iPhone/ iPad
Related: 8/20-28/81 4/20-56/81 4/40-28/81 12/20-28/81 4/20-84/81 4/60-28/81 28/20-28/81