Subtract 4/5 from 21/54
21/54 - 4/5 is -37/90.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 54 and 5 is 270
Next, find the equivalent fraction of both fractional numbers with denominator 270 - For the 1st fraction, since 54 × 5 = 270,
21/54 = 21 × 5/54 × 5 = 105/270 - Likewise, for the 2nd fraction, since 5 × 54 = 270,
4/5 = 4 × 54/5 × 54 = 216/270 - Subtract the two like fractions:
105/270 - 216/270 = 105 - 216/270 = -111/270 - After reducing the fraction, the answer is -37/90
MathStep (Works offline)
Download our mobile app and learn to work with fractions in your own time:
Android and iPhone/ iPad
Related: 42/54-4/5 21/54-8/5 21/54-4/10 63/54-4/5 21/54-12/5 21/54-4/15 21/54-20/5 21/54-4/25 21/54-28/5 21/54-4/35