Subtract 15/21 from 72/4
1st number: 18 0/4, 2nd number: 15/21
72/4 - 15/21 is 121/7.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 4 and 21 is 84
Next, find the equivalent fraction of both fractional numbers with denominator 84 - For the 1st fraction, since 4 × 21 = 84,
72/4 = 72 × 21/4 × 21 = 1512/84 - Likewise, for the 2nd fraction, since 21 × 4 = 84,
15/21 = 15 × 4/21 × 4 = 60/84 - Subtract the two like fractions:
1512/84 - 60/84 = 1512 - 60/84 = 1452/84 - After reducing the fraction, the answer is 121/7
- In mixed form: 172/7
MathStep (Works offline)
Download our mobile app and learn to work with fractions in your own time:
Android and iPhone/ iPad
Related: 72/4-30/21 72/8-15/21 72/4-15/42 72/4-45/21 72/12-15/21 72/4-15/63 72/4-75/21 72/20-15/21 72/28-15/21