Subtract 24/40 from 21/30
21/30 - 24/40 is 1/10.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 30 and 40 is 120
Next, find the equivalent fraction of both fractional numbers with denominator 120 - For the 1st fraction, since 30 × 4 = 120,
21/30 = 21 × 4/30 × 4 = 84/120 - Likewise, for the 2nd fraction, since 40 × 3 = 120,
24/40 = 24 × 3/40 × 3 = 72/120 - Subtract the two like fractions:
84/120 - 72/120 = 84 - 72/120 = 12/120 - After reducing the fraction, the answer is 1/10
MathStep (Works offline)
Download our mobile app and learn to work with fractions in your own time:
Android and iPhone/ iPad
Related: 42/30-24/40 21/30-48/40 21/60-24/40 21/30-24/80 63/30-24/40 21/30-72/40 21/90-24/40