Subtract 81/42 from 28/12
1st number: 2 4/12, 2nd number: 1 39/42
28/12 - 81/42 is 17/42.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 12 and 42 is 84
Next, find the equivalent fraction of both fractional numbers with denominator 84 - For the 1st fraction, since 12 × 7 = 84,
28/12 = 28 × 7/12 × 7 = 196/84 - Likewise, for the 2nd fraction, since 42 × 2 = 84,
81/42 = 81 × 2/42 × 2 = 162/84 - Subtract the two like fractions:
196/84 - 162/84 = 196 - 162/84 = 34/84 - After reducing the fraction, the answer is 17/42
MathStep (Works offline)
Download our mobile app and learn to work with fractions in your own time:
Android and iPhone/ iPad
Related: 56/12-81/42 28/24-81/42 28/12-81/84 84/12-81/42 28/36-81/42 28/60-81/42 28/84-81/42