Subtract 7/84 from 28/21
1st number: 1 7/21, 2nd number: 7/84
28/21 - 7/84 is 5/4.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 21 and 84 is 84
Next, find the equivalent fraction of both fractional numbers with denominator 84 - For the 1st fraction, since 21 × 4 = 84,
28/21 = 28 × 4/21 × 4 = 112/84 - Likewise, for the 2nd fraction, since 84 × 1 = 84,
7/84 = 7 × 1/84 × 1 = 7/84 - Subtract the two like fractions:
112/84 - 7/84 = 112 - 7/84 = 105/84 - After reducing the fraction, the answer is 5/4
- In mixed form: 11/4
MathStep (Works offline)
Download our mobile app and learn to work with fractions in your own time:
Android and iPhone/ iPad
Related: 56/21-7/84 28/21-14/84 28/42-7/84 84/21-7/84 28/21-21/84 28/63-7/84 28/21-35/84 28/21-49/84