Subtract 36/18 from 20/21
1st number: 20/21, 2nd number: 2 0/18
20/21 - 36/18 is -22/21.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 21 and 18 is 126
Next, find the equivalent fraction of both fractional numbers with denominator 126 - For the 1st fraction, since 21 × 6 = 126,
20/21 = 20 × 6/21 × 6 = 120/126 - Likewise, for the 2nd fraction, since 18 × 7 = 126,
36/18 = 36 × 7/18 × 7 = 252/126 - Subtract the two like fractions:
120/126 - 252/126 = 120 - 252/126 = -132/126 - After reducing the fraction, the answer is -22/21
MathStep (Works offline)
Download our mobile app and learn to work with fractions in your own time:
Android and iPhone/ iPad
Related: 40/21-36/18 20/21-72/18 20/42-36/18 60/21-36/18 20/63-36/18 20/21-36/54 20/21-36/90