Subtract 6/54 from 21/42
21/42 - 6/54 is 7/18.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 42 and 54 is 378
Next, find the equivalent fraction of both fractional numbers with denominator 378 - For the 1st fraction, since 42 × 9 = 378,
21/42 = 21 × 9/42 × 9 = 189/378 - Likewise, for the 2nd fraction, since 54 × 7 = 378,
6/54 = 6 × 7/54 × 7 = 42/378 - Subtract the two like fractions:
189/378 - 42/378 = 189 - 42/378 = 147/378 - After reducing the fraction, the answer is 7/18
MathStep (Works offline)
Download our mobile app and learn to work with fractions in your own time:
Android and iPhone/ iPad
Related: 21/42-12/54 21/84-6/54 63/42-6/54 21/42-18/54 21/42-30/54 21/42-42/54