Subtract 28/20 from 7/45
1st number: 7/45, 2nd number: 1 8/20
7/45 - 28/20 is -56/45.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 45 and 20 is 180
Next, find the equivalent fraction of both fractional numbers with denominator 180 - For the 1st fraction, since 45 × 4 = 180,
7/45 = 7 × 4/45 × 4 = 28/180 - Likewise, for the 2nd fraction, since 20 × 9 = 180,
28/20 = 28 × 9/20 × 9 = 252/180 - Subtract the two like fractions:
28/180 - 252/180 = 28 - 252/180 = -224/180 - After reducing the fraction, the answer is -56/45
MathStep (Works offline)
Download our mobile app and learn to work with fractions in your own time:
Android and iPhone/ iPad
Related: 14/45-28/20 7/45-56/20 7/90-28/20 7/45-28/40 21/45-28/20 7/45-84/20 7/45-28/60 35/45-28/20 49/45-28/20