Subtract 42/21 from 9/84
1st number: 9/84, 2nd number: 2 0/21
9/84 - 42/21 is -53/28.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 84 and 21 is 84
Next, find the equivalent fraction of both fractional numbers with denominator 84 - For the 1st fraction, since 84 × 1 = 84,
9/84 = 9 × 1/84 × 1 = 9/84 - Likewise, for the 2nd fraction, since 21 × 4 = 84,
42/21 = 42 × 4/21 × 4 = 168/84 - Subtract the two like fractions:
9/84 - 168/84 = 9 - 168/84 = -159/84 - After reducing the fraction, the answer is -53/28
MathStep (Works offline)
Download our mobile app and learn to work with fractions in your own time:
Android and iPhone/ iPad
Related: 18/84-42/21 9/84-84/21 27/84-42/21 9/84-42/63 45/84-42/21 63/84-42/21