Subtract 6/20 from 21/84
21/84 - 6/20 is -1/20.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 84 and 20 is 420
Next, find the equivalent fraction of both fractional numbers with denominator 420 - For the 1st fraction, since 84 × 5 = 420,
21/84 = 21 × 5/84 × 5 = 105/420 - Likewise, for the 2nd fraction, since 20 × 21 = 420,
6/20 = 6 × 21/20 × 21 = 126/420 - Subtract the two like fractions:
105/420 - 126/420 = 105 - 126/420 = -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: 42/84-6/20 21/84-12/20 21/84-6/40 63/84-6/20 21/84-18/20 21/84-6/60 21/84-30/20 21/84-42/20