Subtract 9/21 from 90/72
1st number: 1 18/72, 2nd number: 9/21
90/72 - 9/21 is 23/28.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 72 and 21 is 504
Next, find the equivalent fraction of both fractional numbers with denominator 504 - For the 1st fraction, since 72 × 7 = 504,
90/72 = 90 × 7/72 × 7 = 630/504 - Likewise, for the 2nd fraction, since 21 × 24 = 504,
9/21 = 9 × 24/21 × 24 = 216/504 - Subtract the two like fractions:
630/504 - 216/504 = 630 - 216/504 = 414/504 - After reducing the fraction, the answer is 23/28
MathStep (Works offline)
Download our mobile app and learn to work with fractions in your own time:
Android and iPhone/ iPad
Related: 90/72-18/21 90/72-9/42 90/72-27/21 90/72-9/63 90/72-45/21 90/72-63/21