Subtract 45/24 from 21/12
1st number: 1 9/12, 2nd number: 1 21/24
21/12 - 45/24 is -1/8.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 12 and 24 is 24
Next, find the equivalent fraction of both fractional numbers with denominator 24 - For the 1st fraction, since 12 × 2 = 24,
21/12 = 21 × 2/12 × 2 = 42/24 - Likewise, for the 2nd fraction, since 24 × 1 = 24,
45/24 = 45 × 1/24 × 1 = 45/24 - Subtract the two like fractions:
42/24 - 45/24 = 42 - 45/24 = -3/24 - After reducing the fraction, the answer is -1/8
MathStep (Works offline)
Download our mobile app and learn to work with fractions in your own time:
Android and iPhone/ iPad
Related: 42/12-45/24 21/12-90/24 21/24-45/24 21/12-45/48 63/12-45/24 21/36-45/24 21/12-45/72 21/60-45/24 21/84-45/24