Subtract 45/40 from 21/2
1st number: 10 1/2, 2nd number: 1 5/40
21/2 - 45/40 is 75/8.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 2 and 40 is 40
Next, find the equivalent fraction of both fractional numbers with denominator 40 - For the 1st fraction, since 2 × 20 = 40,
21/2 = 21 × 20/2 × 20 = 420/40 - Likewise, for the 2nd fraction, since 40 × 1 = 40,
45/40 = 45 × 1/40 × 1 = 45/40 - Subtract the two like fractions:
420/40 - 45/40 = 420 - 45/40 = 375/40 - After reducing the fraction, the answer is 75/8
- In mixed form: 93/8
MathStep (Works offline)
Download our mobile app and learn to work with fractions in your own time:
Android and iPhone/ iPad
Related: 42/2-45/40 21/2-90/40 21/4-45/40 21/2-45/80 63/2-45/40 21/6-45/40 21/10-45/40 21/14-45/40