Subtract 21/7 from 20/4
1st number: 5 0/4, 2nd number: 3 0/7
20/4 - 21/7 is 2/1.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 4 and 7 is 28
Next, find the equivalent fraction of both fractional numbers with denominator 28 - For the 1st fraction, since 4 × 7 = 28,
20/4 = 20 × 7/4 × 7 = 140/28 - Likewise, for the 2nd fraction, since 7 × 4 = 28,
21/7 = 21 × 4/7 × 4 = 84/28 - Subtract the two like fractions:
140/28 - 84/28 = 140 - 84/28 = 56/28 - After reducing the fraction, the answer is 2/1
MathStep (Works offline)
Download our mobile app and learn to work with fractions in your own time:
Android and iPhone/ iPad
Related: 40/4-21/7 20/4-42/7 20/8-21/7 20/4-21/14 60/4-21/7 20/4-63/7 20/12-21/7 20/4-21/35 20/28-21/7 20/4-21/49