Subtract 42/7 from 45/12
1st number: 3 9/12, 2nd number: 6 0/7
45/12 - 42/7 is -9/4.
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,
45/12 = 45 × 7/12 × 7 = 315/84 - Likewise, for the 2nd fraction, since 7 × 12 = 84,
42/7 = 42 × 12/7 × 12 = 504/84 - Subtract the two like fractions:
315/84 - 504/84 = 315 - 504/84 = -189/84 - After reducing the fraction, the answer is -9/4
MathStep (Works offline)
Download our mobile app and learn to work with fractions in your own time:
Android and iPhone/ iPad
Related: 90/12-42/7 45/12-84/7 45/24-42/7 45/12-42/14 45/36-42/7 45/12-42/21 45/60-42/7 45/12-42/35 45/84-42/7 45/12-42/49