Subtract 30/56 from 20/21
20/21 - 30/56 is 5/12.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 21 and 56 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 56 × 3 = 168,
30/56 = 30 × 3/56 × 3 = 90/168 - Subtract the two like fractions:
160/168 - 90/168 = 160 - 90/168 = 70/168 - After reducing the fraction, the answer is 5/12
MathStep (Works offline)
Download our mobile app and learn to work with fractions in your own time:
Android and iPhone/ iPad
Related: 40/21-30/56 20/21-60/56 20/42-30/56 60/21-30/56 20/21-90/56 20/63-30/56