Subtract 36/18 from 21/12
1st number: 1 9/12, 2nd number: 2 0/18
21/12 - 36/18 is -1/4.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 12 and 18 is 36
Next, find the equivalent fraction of both fractional numbers with denominator 36 - For the 1st fraction, since 12 × 3 = 36,
21/12 = 21 × 3/12 × 3 = 63/36 - Likewise, for the 2nd fraction, since 18 × 2 = 36,
36/18 = 36 × 2/18 × 2 = 72/36 - Subtract the two like fractions:
63/36 - 72/36 = 63 - 72/36 = -9/36 - After reducing the fraction, the answer is -1/4
MathStep (Works offline)
Download our mobile app and learn to work with fractions in your own time:
Android and iPhone/ iPad
Related: 42/12-36/18 21/12-72/18 21/24-36/18 63/12-36/18 21/36-36/18 21/12-36/54 21/60-36/18 21/12-36/90 21/84-36/18