Subtract 3/40 from 21/48
21/48 - 3/40 is 29/80.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 48 and 40 is 240
Next, find the equivalent fraction of both fractional numbers with denominator 240 - For the 1st fraction, since 48 × 5 = 240,
21/48 = 21 × 5/48 × 5 = 105/240 - Likewise, for the 2nd fraction, since 40 × 6 = 240,
3/40 = 3 × 6/40 × 6 = 18/240 - Subtract the two like fractions:
105/240 - 18/240 = 105 - 18/240 = 87/240 - After reducing the fraction, the answer is 29/80
MathStep (Works offline)
Download our mobile app and learn to work with fractions in your own time:
Android and iPhone/ iPad
Related: 42/48-3/40 21/48-6/40 21/96-3/40 21/48-3/80 63/48-3/40 21/48-9/40 21/48-15/40 21/48-21/40