Subtract 20/32 from 8/42
8/42 - 20/32 is -73/168.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 42 and 32 is 672
Next, find the equivalent fraction of both fractional numbers with denominator 672 - For the 1st fraction, since 42 × 16 = 672,
8/42 = 8 × 16/42 × 16 = 128/672 - Likewise, for the 2nd fraction, since 32 × 21 = 672,
20/32 = 20 × 21/32 × 21 = 420/672 - Subtract the two like fractions:
128/672 - 420/672 = 128 - 420/672 = -292/672 - After reducing the fraction, the answer is -73/168
MathStep (Works offline)
Download our mobile app and learn to work with fractions in your own time:
Android and iPhone/ iPad
Related: 16/42-20/32 8/42-40/32 8/84-20/32 8/42-20/64 24/42-20/32 8/42-60/32 8/42-20/96 40/42-20/32 56/42-20/32