Subtract 45/30 from 10/21
1st number: 10/21, 2nd number: 1 15/30
10/21 - 45/30 is -43/42.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 21 and 30 is 210
Next, find the equivalent fraction of both fractional numbers with denominator 210 - For the 1st fraction, since 21 × 10 = 210,
10/21 = 10 × 10/21 × 10 = 100/210 - Likewise, for the 2nd fraction, since 30 × 7 = 210,
45/30 = 45 × 7/30 × 7 = 315/210 - Subtract the two like fractions:
100/210 - 315/210 = 100 - 315/210 = -215/210 - After reducing the fraction, the answer is -43/42
MathStep (Works offline)
Download our mobile app and learn to work with fractions in your own time:
Android and iPhone/ iPad
Related: 20/21-45/30 10/21-90/30 10/42-45/30 10/21-45/60 30/21-45/30 10/63-45/30 10/21-45/90 50/21-45/30 70/21-45/30