Subtract 3/21 from 7/54
7/54 - 3/21 is -5/378.
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,
7/54 = 7 × 7/54 × 7 = 49/378 - Likewise, for the 2nd fraction, since 21 × 18 = 378,
3/21 = 3 × 18/21 × 18 = 54/378 - Subtract the two like fractions:
49/378 - 54/378 = 49 - 54/378 = -5/378
MathStep (Works offline)
Download our mobile app and learn to work with fractions in your own time:
Android and iPhone/ iPad
Related: 14/54-3/21 7/54-6/21 7/54-3/42 21/54-3/21 7/54-9/21 7/54-3/63 35/54-3/21 7/54-15/21 49/54-3/21