Subtract 21/90 from 84/18
1st number: 4 12/18, 2nd number: 21/90
84/18 - 21/90 is 133/30.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 18 and 90 is 90
Next, find the equivalent fraction of both fractional numbers with denominator 90 - For the 1st fraction, since 18 × 5 = 90,
84/18 = 84 × 5/18 × 5 = 420/90 - Likewise, for the 2nd fraction, since 90 × 1 = 90,
21/90 = 21 × 1/90 × 1 = 21/90 - Subtract the two like fractions:
420/90 - 21/90 = 420 - 21/90 = 399/90 - After reducing the fraction, the answer is 133/30
- In mixed form: 413/30
MathStep (Works offline)
Download our mobile app and learn to work with fractions in your own time:
Android and iPhone/ iPad
Related: 84/18-42/90 84/36-21/90 84/18-63/90 84/54-21/90 84/90-21/90