Subtract 18/21 from 50/60
50/60 - 18/21 is -1/42.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 60 and 21 is 420
Next, find the equivalent fraction of both fractional numbers with denominator 420 - For the 1st fraction, since 60 × 7 = 420,
50/60 = 50 × 7/60 × 7 = 350/420 - Likewise, for the 2nd fraction, since 21 × 20 = 420,
18/21 = 18 × 20/21 × 20 = 360/420 - Subtract the two like fractions:
350/420 - 360/420 = 350 - 360/420 = -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: 50/60-36/21 50/60-18/42 50/60-54/21 50/60-18/63 50/60-90/21