Subtract 30/60 from 20/42
20/42 - 30/60 is -1/42.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 42 and 60 is 420
Next, find the equivalent fraction of both fractional numbers with denominator 420 - For the 1st fraction, since 42 × 10 = 420,
20/42 = 20 × 10/42 × 10 = 200/420 - Likewise, for the 2nd fraction, since 60 × 7 = 420,
30/60 = 30 × 7/60 × 7 = 210/420 - Subtract the two like fractions:
200/420 - 210/420 = 200 - 210/420 = -10/420 - After reducing the fraction, the answer is -1/42
MathStep (Works offline)
Download our mobile app and learn to work with fractions in your own time:
Android and iPhone/ iPad
Related: 40/42-30/60 20/84-30/60 60/42-30/60 20/42-90/60