Subtract 1/21 from 28/12
1st number: 2 4/12, 2nd number: 1/21
28/12 - 1/21 is 16/7.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 12 and 21 is 84
Next, find the equivalent fraction of both fractional numbers with denominator 84 - For the 1st fraction, since 12 × 7 = 84,
28/12 = 28 × 7/12 × 7 = 196/84 - Likewise, for the 2nd fraction, since 21 × 4 = 84,
1/21 = 1 × 4/21 × 4 = 4/84 - Subtract the two like fractions:
196/84 - 4/84 = 196 - 4/84 = 192/84 - After reducing the fraction, the answer is 16/7
- In mixed form: 22/7
MathStep (Works offline)
Download our mobile app and learn to work with fractions in your own time:
Android and iPhone/ iPad
Related: 56/12-1/21 28/12-2/21 28/24-1/21 28/12-1/42 84/12-1/21 28/12-3/21 28/36-1/21 28/12-1/63 28/12-5/21 28/60-1/21 28/12-7/21 28/84-1/21