Subtract 42/5 from 81/2
1st number: 40 1/2, 2nd number: 8 2/5
81/2 - 42/5 is 321/10.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 2 and 5 is 10
Next, find the equivalent fraction of both fractional numbers with denominator 10 - For the 1st fraction, since 2 × 5 = 10,
81/2 = 81 × 5/2 × 5 = 405/10 - Likewise, for the 2nd fraction, since 5 × 2 = 10,
42/5 = 42 × 2/5 × 2 = 84/10 - Subtract the two like fractions:
405/10 - 84/10 = 405 - 84/10 = 321/10 - In mixed form: 321/10
MathStep (Works offline)
Download our mobile app and learn to work with fractions in your own time:
Android and iPhone/ iPad
Related: 81/2-84/5 81/4-42/5 81/2-42/10 81/6-42/5 81/2-42/15 81/10-42/5 81/2-42/25 81/14-42/5 81/2-42/35