Subtract 1/21 from 27/54
27/54 - 1/21 is 19/42.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 54 and 21 is 378
Next, find the equivalent fraction of both fractional numbers with denominator 378 - For the 1st fraction, since 54 × 7 = 378,
27/54 = 27 × 7/54 × 7 = 189/378 - Likewise, for the 2nd fraction, since 21 × 18 = 378,
1/21 = 1 × 18/21 × 18 = 18/378 - Subtract the two like fractions:
189/378 - 18/378 = 189 - 18/378 = 171/378 - After reducing the fraction, the answer is 19/42
MathStep (Works offline)
Download our mobile app and learn to work with fractions in your own time:
Android and iPhone/ iPad
Related: 27/54-2/21 27/54-1/42 81/54-1/21 27/54-3/21 27/54-1/63 27/54-5/21 27/54-7/21