Subtract 20/28 from 7/20
7/20 - 20/28 is -51/140.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 20 and 28 is 140
Next, find the equivalent fraction of both fractional numbers with denominator 140 - For the 1st fraction, since 20 × 7 = 140,
7/20 = 7 × 7/20 × 7 = 49/140 - Likewise, for the 2nd fraction, since 28 × 5 = 140,
20/28 = 20 × 5/28 × 5 = 100/140 - Subtract the two like fractions:
49/140 - 100/140 = 49 - 100/140 = -51/140
MathStep (Works offline)
Download our mobile app and learn to work with fractions in your own time:
Android and iPhone/ iPad
Related: 14/20-20/28 7/20-40/28 7/40-20/28 7/20-20/56 21/20-20/28 7/20-60/28 7/60-20/28 7/20-20/84 35/20-20/28 49/20-20/28