Subtract 42/9 from 54/21
1st number: 2 12/21, 2nd number: 4 6/9
54/21 - 42/9 is -44/21.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 21 and 9 is 63
Next, find the equivalent fraction of both fractional numbers with denominator 63 - For the 1st fraction, since 21 × 3 = 63,
54/21 = 54 × 3/21 × 3 = 162/63 - Likewise, for the 2nd fraction, since 9 × 7 = 63,
42/9 = 42 × 7/9 × 7 = 294/63 - Subtract the two like fractions:
162/63 - 294/63 = 162 - 294/63 = -132/63 - After reducing the fraction, the answer is -44/21
MathStep (Works offline)
Download our mobile app and learn to work with fractions in your own time:
Android and iPhone/ iPad
Related: 54/21-84/9 54/42-42/9 54/21-42/18 54/63-42/9 54/21-42/27 54/21-42/45 54/21-42/63