Subtract 9/7 from 20/30
1st number: 20/30, 2nd number: 1 2/7
20/30 - 9/7 is -13/21.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 30 and 7 is 210
Next, find the equivalent fraction of both fractional numbers with denominator 210 - For the 1st fraction, since 30 × 7 = 210,
20/30 = 20 × 7/30 × 7 = 140/210 - Likewise, for the 2nd fraction, since 7 × 30 = 210,
9/7 = 9 × 30/7 × 30 = 270/210 - Subtract the two like fractions:
140/210 - 270/210 = 140 - 270/210 = -130/210 - After reducing the fraction, the answer is -13/21
MathStep (Works offline)
Download our mobile app and learn to work with fractions in your own time:
Android and iPhone/ iPad
Related: 40/30-9/7 20/30-18/7 20/60-9/7 20/30-9/14 60/30-9/7 20/30-27/7 20/90-9/7 20/30-9/21 20/30-45/7 20/30-9/35 20/30-63/7 20/30-9/49