Subtract 7/21 from 45/18
1st number: 2 9/18, 2nd number: 7/21
45/18 - 7/21 is 13/6.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 18 and 21 is 126
Next, find the equivalent fraction of both fractional numbers with denominator 126 - For the 1st fraction, since 18 × 7 = 126,
45/18 = 45 × 7/18 × 7 = 315/126 - Likewise, for the 2nd fraction, since 21 × 6 = 126,
7/21 = 7 × 6/21 × 6 = 42/126 - Subtract the two like fractions:
315/126 - 42/126 = 315 - 42/126 = 273/126 - After reducing the fraction, the answer is 13/6
- In mixed form: 21/6
MathStep (Works offline)
Download our mobile app and learn to work with fractions in your own time:
Android and iPhone/ iPad
Related: 90/18-7/21 45/18-14/21 45/36-7/21 45/18-7/42 45/54-7/21 45/18-7/63 45/18-35/21 45/90-7/21 45/18-49/21