Subtract 72/21 from 84/3
1st number: 28 0/3, 2nd number: 3 9/21
84/3 - 72/21 is 172/7.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 3 and 21 is 21
Next, find the equivalent fraction of both fractional numbers with denominator 21 - For the 1st fraction, since 3 × 7 = 21,
84/3 = 84 × 7/3 × 7 = 588/21 - Likewise, for the 2nd fraction, since 21 × 1 = 21,
72/21 = 72 × 1/21 × 1 = 72/21 - Subtract the two like fractions:
588/21 - 72/21 = 588 - 72/21 = 516/21 - After reducing the fraction, the answer is 172/7
- In mixed form: 244/7
MathStep (Works offline)
Download our mobile app and learn to work with fractions in your own time:
Android and iPhone/ iPad
Related: 84/6-72/21 84/3-72/42 84/9-72/21 84/3-72/63 84/15-72/21 84/21-72/21