Subtract 20/30 from 18/7
1st number: 2 4/7, 2nd number: 20/30
18/7 - 20/30 is 40/21.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 7 and 30 is 210
Next, find the equivalent fraction of both fractional numbers with denominator 210 - For the 1st fraction, since 7 × 30 = 210,
18/7 = 18 × 30/7 × 30 = 540/210 - Likewise, for the 2nd fraction, since 30 × 7 = 210,
20/30 = 20 × 7/30 × 7 = 140/210 - Subtract the two like fractions:
540/210 - 140/210 = 540 - 140/210 = 400/210 - After reducing the fraction, the answer is 40/21
- In mixed form: 119/21
MathStep (Works offline)
Download our mobile app and learn to work with fractions in your own time:
Android and iPhone/ iPad
Related: 36/7-20/30 18/7-40/30 18/14-20/30 18/7-20/60 54/7-20/30 18/7-60/30 18/21-20/30 18/7-20/90 90/7-20/30 18/35-20/30 18/49-20/30