Subtract 21/42 from 27/60
27/60 - 21/42 is -1/20.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 60 and 42 is 420
Next, find the equivalent fraction of both fractional numbers with denominator 420 - For the 1st fraction, since 60 × 7 = 420,
27/60 = 27 × 7/60 × 7 = 189/420 - Likewise, for the 2nd fraction, since 42 × 10 = 420,
21/42 = 21 × 10/42 × 10 = 210/420 - Subtract the two like fractions:
189/420 - 210/420 = 189 - 210/420 = -21/420 - After reducing the fraction, the answer is -1/20
MathStep (Works offline)
Download our mobile app and learn to work with fractions in your own time:
Android and iPhone/ iPad
Related: 54/60-21/42 27/60-21/84 81/60-21/42 27/60-63/42