Subtract 4/5 from 9/21
9/21 - 4/5 is -13/35.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 21 and 5 is 105
Next, find the equivalent fraction of both fractional numbers with denominator 105 - For the 1st fraction, since 21 × 5 = 105,
9/21 = 9 × 5/21 × 5 = 45/105 - Likewise, for the 2nd fraction, since 5 × 21 = 105,
4/5 = 4 × 21/5 × 21 = 84/105 - Subtract the two like fractions:
45/105 - 84/105 = 45 - 84/105 = -39/105 - After reducing the fraction, the answer is -13/35
MathStep (Works offline)
Download our mobile app and learn to work with fractions in your own time:
Android and iPhone/ iPad
Related: 18/21-4/5 9/21-8/5 9/42-4/5 9/21-4/10 27/21-4/5 9/21-12/5 9/63-4/5 9/21-4/15 45/21-4/5 9/21-20/5 9/21-4/25 63/21-4/5 9/21-28/5 9/21-4/35