Subtract 54/8 from 21/18
1st number: 1 3/18, 2nd number: 6 6/8
21/18 - 54/8 is -67/12.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 18 and 8 is 72
Next, find the equivalent fraction of both fractional numbers with denominator 72 - For the 1st fraction, since 18 × 4 = 72,
21/18 = 21 × 4/18 × 4 = 84/72 - Likewise, for the 2nd fraction, since 8 × 9 = 72,
54/8 = 54 × 9/8 × 9 = 486/72 - Subtract the two like fractions:
84/72 - 486/72 = 84 - 486/72 = -402/72 - After reducing the fraction, the answer is -67/12
MathStep (Works offline)
Download our mobile app and learn to work with fractions in your own time:
Android and iPhone/ iPad
Related: 42/18-54/8 21/36-54/8 21/18-54/16 63/18-54/8 21/54-54/8 21/18-54/24 21/90-54/8 21/18-54/40 21/18-54/56