Subtract 30/24 from 20/21
1st number: 20/21, 2nd number: 1 6/24
20/21 - 30/24 is -25/84.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 21 and 24 is 168
Next, find the equivalent fraction of both fractional numbers with denominator 168 - For the 1st fraction, since 21 × 8 = 168,
20/21 = 20 × 8/21 × 8 = 160/168 - Likewise, for the 2nd fraction, since 24 × 7 = 168,
30/24 = 30 × 7/24 × 7 = 210/168 - Subtract the two like fractions:
160/168 - 210/168 = 160 - 210/168 = -50/168 - After reducing the fraction, the answer is -25/84
MathStep (Works offline)
Download our mobile app and learn to work with fractions in your own time:
Android and iPhone/ iPad
Related: 40/21-30/24 20/21-60/24 20/42-30/24 20/21-30/48 60/21-30/24 20/21-90/24 20/63-30/24 20/21-30/72