Subtract 42/9 from 28/20
1st number: 1 8/20, 2nd number: 4 6/9
28/20 - 42/9 is -49/15.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 20 and 9 is 180
Next, find the equivalent fraction of both fractional numbers with denominator 180 - For the 1st fraction, since 20 × 9 = 180,
28/20 = 28 × 9/20 × 9 = 252/180 - Likewise, for the 2nd fraction, since 9 × 20 = 180,
42/9 = 42 × 20/9 × 20 = 840/180 - Subtract the two like fractions:
252/180 - 840/180 = 252 - 840/180 = -588/180 - After reducing the fraction, the answer is -49/15
MathStep (Works offline)
Download our mobile app and learn to work with fractions in your own time:
Android and iPhone/ iPad
Related: 56/20-42/9 28/20-84/9 28/40-42/9 28/20-42/18 84/20-42/9 28/60-42/9 28/20-42/27 28/20-42/45 28/20-42/63