Subtract 3/15 from 30/40
30/40 - 3/15 is 11/20.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 40 and 15 is 120
Next, find the equivalent fraction of both fractional numbers with denominator 120 - For the 1st fraction, since 40 × 3 = 120,
30/40 = 30 × 3/40 × 3 = 90/120 - Likewise, for the 2nd fraction, since 15 × 8 = 120,
3/15 = 3 × 8/15 × 8 = 24/120 - Subtract the two like fractions:
90/120 - 24/120 = 90 - 24/120 = 66/120 - After reducing the fraction, the answer is 11/20
MathStep (Works offline)
Download our mobile app and learn to work with fractions in your own time:
Android and iPhone/ iPad
Related: 60/40-3/15 30/40-6/15 30/80-3/15 30/40-3/30 90/40-3/15 30/40-9/15 30/40-3/45 30/40-3/75 30/40-21/15