Subtract 40/20 from 18/12
1st number: 1 6/12, 2nd number: 2 0/20
18/12 - 40/20 is -1/2.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 12 and 20 is 60
Next, find the equivalent fraction of both fractional numbers with denominator 60 - For the 1st fraction, since 12 × 5 = 60,
18/12 = 18 × 5/12 × 5 = 90/60 - Likewise, for the 2nd fraction, since 20 × 3 = 60,
40/20 = 40 × 3/20 × 3 = 120/60 - Subtract the two like fractions:
90/60 - 120/60 = 90 - 120/60 = -30/60 - After reducing the fraction, the answer is -1/2
MathStep (Works offline)
Download our mobile app and learn to work with fractions in your own time:
Android and iPhone/ iPad
Related: 36/12-40/20 18/12-80/20 18/24-40/20 54/12-40/20 18/36-40/20 18/12-40/60 90/12-40/20 18/60-40/20 18/84-40/20