Subtract 42/7 from 20/12
1st number: 1 8/12, 2nd number: 6 0/7
20/12 - 42/7 is -13/3.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 12 and 7 is 84
Next, find the equivalent fraction of both fractional numbers with denominator 84 - For the 1st fraction, since 12 × 7 = 84,
20/12 = 20 × 7/12 × 7 = 140/84 - Likewise, for the 2nd fraction, since 7 × 12 = 84,
42/7 = 42 × 12/7 × 12 = 504/84 - Subtract the two like fractions:
140/84 - 504/84 = 140 - 504/84 = -364/84 - After reducing the fraction, the answer is -13/3
MathStep (Works offline)
Download our mobile app and learn to work with fractions in your own time:
Android and iPhone/ iPad
Related: 40/12-42/7 20/12-84/7 20/24-42/7 20/12-42/14 60/12-42/7 20/36-42/7 20/12-42/21 20/60-42/7 20/12-42/35 20/84-42/7 20/12-42/49