Subtract 18/63 from 4/42
4/42 - 18/63 is -4/21.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 42 and 63 is 126
Next, find the equivalent fraction of both fractional numbers with denominator 126 - For the 1st fraction, since 42 × 3 = 126,
4/42 = 4 × 3/42 × 3 = 12/126 - Likewise, for the 2nd fraction, since 63 × 2 = 126,
18/63 = 18 × 2/63 × 2 = 36/126 - Subtract the two like fractions:
12/126 - 36/126 = 12 - 36/126 = -24/126 - After reducing the fraction, the answer is -4/21
MathStep (Works offline)
Download our mobile app and learn to work with fractions in your own time:
Android and iPhone/ iPad
Related: 8/42-18/63 4/42-36/63 4/84-18/63 12/42-18/63 4/42-54/63 20/42-18/63 4/42-90/63 28/42-18/63