Subtract 6/8 from 21/72
21/72 - 6/8 is -11/24.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 72 and 8 is 72
Next, find the equivalent fraction of both fractional numbers with denominator 72 - For the 1st fraction, since 72 × 1 = 72,
21/72 = 21 × 1/72 × 1 = 21/72 - Likewise, for the 2nd fraction, since 8 × 9 = 72,
6/8 = 6 × 9/8 × 9 = 54/72 - Subtract the two like fractions:
21/72 - 54/72 = 21 - 54/72 = -33/72 - After reducing the fraction, the answer is -11/24
MathStep (Works offline)
Download our mobile app and learn to work with fractions in your own time:
Android and iPhone/ iPad
Related: 42/72-6/8 21/72-12/8 21/72-6/16 63/72-6/8 21/72-18/8 21/72-6/24 21/72-30/8 21/72-6/40 21/72-42/8 21/72-6/56