Subtract 18/30 from 21/50
21/50 - 18/30 is -9/50.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 50 and 30 is 150
Next, find the equivalent fraction of both fractional numbers with denominator 150 - For the 1st fraction, since 50 × 3 = 150,
21/50 = 21 × 3/50 × 3 = 63/150 - Likewise, for the 2nd fraction, since 30 × 5 = 150,
18/30 = 18 × 5/30 × 5 = 90/150 - Subtract the two like fractions:
63/150 - 90/150 = 63 - 90/150 = -27/150 - After reducing the fraction, the answer is -9/50
MathStep (Works offline)
Download our mobile app and learn to work with fractions in your own time:
Android and iPhone/ iPad
Related: 42/50-18/30 21/50-36/30 21/50-18/60 63/50-18/30 21/50-54/30 21/50-18/90 21/50-90/30