Subtract 20/63 from 12/42
12/42 - 20/63 is -2/63.
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,
12/42 = 12 × 3/42 × 3 = 36/126 - Likewise, for the 2nd fraction, since 63 × 2 = 126,
20/63 = 20 × 2/63 × 2 = 40/126 - Subtract the two like fractions:
36/126 - 40/126 = 36 - 40/126 = -4/126 - After reducing the fraction, the answer is -2/63
MathStep (Works offline)
Download our mobile app and learn to work with fractions in your own time:
Android and iPhone/ iPad
Related: 24/42-20/63 12/42-40/63 12/84-20/63 36/42-20/63 12/42-60/63 60/42-20/63 84/42-20/63