Subtract 9/21 from 20/50
20/50 - 9/21 is -1/35.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 50 and 21 is 1050
Next, find the equivalent fraction of both fractional numbers with denominator 1050 - For the 1st fraction, since 50 × 21 = 1050,
20/50 = 20 × 21/50 × 21 = 420/1050 - Likewise, for the 2nd fraction, since 21 × 50 = 1050,
9/21 = 9 × 50/21 × 50 = 450/1050 - Subtract the two like fractions:
420/1050 - 450/1050 = 420 - 450/1050 = -30/1050 - After reducing the fraction, the answer is -1/35
MathStep (Works offline)
Download our mobile app and learn to work with fractions in your own time:
Android and iPhone/ iPad
Related: 40/50-9/21 20/50-18/21 20/50-9/42 60/50-9/21 20/50-27/21 20/50-9/63 20/50-45/21 20/50-63/21