Subtract 45/20 from 42/18
1st number: 2 6/18, 2nd number: 2 5/20
42/18 - 45/20 is 1/12.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 18 and 20 is 180
Next, find the equivalent fraction of both fractional numbers with denominator 180 - For the 1st fraction, since 18 × 10 = 180,
42/18 = 42 × 10/18 × 10 = 420/180 - Likewise, for the 2nd fraction, since 20 × 9 = 180,
45/20 = 45 × 9/20 × 9 = 405/180 - Subtract the two like fractions:
420/180 - 405/180 = 420 - 405/180 = 15/180 - After reducing the fraction, the answer is 1/12
MathStep (Works offline)
Download our mobile app and learn to work with fractions in your own time:
Android and iPhone/ iPad
Related: 84/18-45/20 42/18-90/20 42/36-45/20 42/18-45/40 42/54-45/20 42/18-45/60 42/90-45/20