Subtract 9/21 from 3/10
3/10 - 9/21 is -9/70.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 10 and 21 is 210
Next, find the equivalent fraction of both fractional numbers with denominator 210 - For the 1st fraction, since 10 × 21 = 210,
3/10 = 3 × 21/10 × 21 = 63/210 - Likewise, for the 2nd fraction, since 21 × 10 = 210,
9/21 = 9 × 10/21 × 10 = 90/210 - Subtract the two like fractions:
63/210 - 90/210 = 63 - 90/210 = -27/210 - After reducing the fraction, the answer is -9/70
MathStep (Works offline)
Download our mobile app and learn to work with fractions in your own time:
Android and iPhone/ iPad
Related: 6/10-9/21 3/10-18/21 3/20-9/21 3/10-9/42 9/10-9/21 3/10-27/21 3/30-9/21 3/10-9/63 15/10-9/21 3/10-45/21 3/50-9/21 21/10-9/21 3/10-63/21 3/70-9/21