Subtract 21/45 from 10/30
10/30 - 21/45 is -2/15.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 30 and 45 is 90
Next, find the equivalent fraction of both fractional numbers with denominator 90 - For the 1st fraction, since 30 × 3 = 90,
10/30 = 10 × 3/30 × 3 = 30/90 - Likewise, for the 2nd fraction, since 45 × 2 = 90,
21/45 = 21 × 2/45 × 2 = 42/90 - Subtract the two like fractions:
30/90 - 42/90 = 30 - 42/90 = -12/90 - After reducing the fraction, the answer is -2/15
MathStep (Works offline)
Download our mobile app and learn to work with fractions in your own time:
Android and iPhone/ iPad
Related: 20/30-21/45 10/30-42/45 10/60-21/45 10/30-21/90 10/30-63/45 10/90-21/45 50/30-21/45 70/30-21/45