Subtract 21/84 from 20/30
20/30 - 21/84 is 5/12.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 30 and 84 is 420
Next, find the equivalent fraction of both fractional numbers with denominator 420 - For the 1st fraction, since 30 × 14 = 420,
20/30 = 20 × 14/30 × 14 = 280/420 - Likewise, for the 2nd fraction, since 84 × 5 = 420,
21/84 = 21 × 5/84 × 5 = 105/420 - Subtract the two like fractions:
280/420 - 105/420 = 280 - 105/420 = 175/420 - After reducing the fraction, the answer is 5/12
MathStep (Works offline)
Download our mobile app and learn to work with fractions in your own time:
Android and iPhone/ iPad
Related: 40/30-21/84 20/30-42/84 20/60-21/84 60/30-21/84 20/30-63/84 20/90-21/84