Subtract 42/80 from 90/36
1st number: 2 18/36, 2nd number: 42/80
90/36 - 42/80 is 79/40.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 36 and 80 is 720
Next, find the equivalent fraction of both fractional numbers with denominator 720 - For the 1st fraction, since 36 × 20 = 720,
90/36 = 90 × 20/36 × 20 = 1800/720 - Likewise, for the 2nd fraction, since 80 × 9 = 720,
42/80 = 42 × 9/80 × 9 = 378/720 - Subtract the two like fractions:
1800/720 - 378/720 = 1800 - 378/720 = 1422/720 - After reducing the fraction, the answer is 79/40
- In mixed form: 139/40
MathStep (Works offline)
Download our mobile app and learn to work with fractions in your own time:
Android and iPhone/ iPad
Related: 90/36-84/80 90/72-42/80