Subtract 42/21 from 3/54
1st number: 3/54, 2nd number: 2 0/21
3/54 - 42/21 is -35/18.
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,
3/54 = 3 × 7/54 × 7 = 21/378 - Likewise, for the 2nd fraction, since 21 × 18 = 378,
42/21 = 42 × 18/21 × 18 = 756/378 - Subtract the two like fractions:
21/378 - 756/378 = 21 - 756/378 = -735/378 - After reducing the fraction, the answer is -35/18
MathStep (Works offline)
Download our mobile app and learn to work with fractions in your own time:
Android and iPhone/ iPad
Related: 6/54-42/21 3/54-84/21 9/54-42/21 3/54-42/63 15/54-42/21 21/54-42/21