Subtract 40/45 from 7/20
7/20 - 40/45 is -97/180.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 20 and 45 is 180
Next, find the equivalent fraction of both fractional numbers with denominator 180 - For the 1st fraction, since 20 × 9 = 180,
7/20 = 7 × 9/20 × 9 = 63/180 - Likewise, for the 2nd fraction, since 45 × 4 = 180,
40/45 = 40 × 4/45 × 4 = 160/180 - Subtract the two like fractions:
63/180 - 160/180 = 63 - 160/180 = -97/180
MathStep (Works offline)
Download our mobile app and learn to work with fractions in your own time:
Android and iPhone/ iPad
Related: 14/20-40/45 7/20-80/45 7/40-40/45 7/20-40/90 21/20-40/45 7/60-40/45 35/20-40/45 49/20-40/45