Subtract 45/18 from 3/42
1st number: 3/42, 2nd number: 2 9/18
3/42 - 45/18 is -17/7.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 42 and 18 is 126
Next, find the equivalent fraction of both fractional numbers with denominator 126 - For the 1st fraction, since 42 × 3 = 126,
3/42 = 3 × 3/42 × 3 = 9/126 - Likewise, for the 2nd fraction, since 18 × 7 = 126,
45/18 = 45 × 7/18 × 7 = 315/126 - Subtract the two like fractions:
9/126 - 315/126 = 9 - 315/126 = -306/126 - After reducing the fraction, the answer is -17/7
MathStep (Works offline)
Download our mobile app and learn to work with fractions in your own time:
Android and iPhone/ iPad
Related: 6/42-45/18 3/42-90/18 3/84-45/18 3/42-45/36 9/42-45/18 3/42-45/54 15/42-45/18 3/42-45/90 21/42-45/18