Subtract 40/45 from 21/2
1st number: 10 1/2, 2nd number: 40/45
21/2 - 40/45 is 173/18.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 2 and 45 is 90
Next, find the equivalent fraction of both fractional numbers with denominator 90 - For the 1st fraction, since 2 × 45 = 90,
21/2 = 21 × 45/2 × 45 = 945/90 - Likewise, for the 2nd fraction, since 45 × 2 = 90,
40/45 = 40 × 2/45 × 2 = 80/90 - Subtract the two like fractions:
945/90 - 80/90 = 945 - 80/90 = 865/90 - After reducing the fraction, the answer is 173/18
- In mixed form: 911/18
MathStep (Works offline)
Download our mobile app and learn to work with fractions in your own time:
Android and iPhone/ iPad
Related: 42/2-40/45 21/2-80/45 21/4-40/45 21/2-40/90 63/2-40/45 21/6-40/45 21/10-40/45 21/14-40/45