Subtract 21/12 from 21/4
1st number: 5 1/4, 2nd number: 1 9/12
21/4 - 21/12 is 7/2.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 4 and 12 is 12
Next, find the equivalent fraction of both fractional numbers with denominator 12 - For the 1st fraction, since 4 × 3 = 12,
21/4 = 21 × 3/4 × 3 = 63/12 - Likewise, for the 2nd fraction, since 12 × 1 = 12,
21/12 = 21 × 1/12 × 1 = 21/12 - Subtract the two like fractions:
63/12 - 21/12 = 63 - 21/12 = 42/12 - After reducing the fraction, the answer is 7/2
- In mixed form: 31/2
MathStep (Works offline)
Download our mobile app and learn to work with fractions in your own time:
Android and iPhone/ iPad
Related: 42/4-21/12 21/4-42/12 21/8-21/12 21/4-21/24 63/4-21/12 21/4-63/12 21/12-21/12 21/4-21/36 21/20-21/12 21/4-21/60 21/28-21/12 21/4-21/84