Subtract 42/21 from 5/12
1st number: 5/12, 2nd number: 2 0/21
5/12 - 42/21 is -19/12.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 12 and 21 is 84
Next, find the equivalent fraction of both fractional numbers with denominator 84 - For the 1st fraction, since 12 × 7 = 84,
5/12 = 5 × 7/12 × 7 = 35/84 - Likewise, for the 2nd fraction, since 21 × 4 = 84,
42/21 = 42 × 4/21 × 4 = 168/84 - Subtract the two like fractions:
35/84 - 168/84 = 35 - 168/84 = -133/84 - After reducing the fraction, the answer is -19/12
MathStep (Works offline)
Download our mobile app and learn to work with fractions in your own time:
Android and iPhone/ iPad
Related: 10/12-42/21 5/12-84/21 5/24-42/21 15/12-42/21 5/36-42/21 5/12-42/63 25/12-42/21 5/60-42/21 35/12-42/21 5/84-42/21