Compare 9/90 and 81/21
1st number: 9/90, 2nd number: 3 18/21
9/90 is smaller than 81/21
Steps for comparing fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 90 and 21 is 630
Next, find the equivalent fraction of both fractional numbers with denominator 630 - For the 1st fraction, since 90 × 7 = 630,
9/90 = 9 × 7/90 × 7 = 63/630 - Likewise, for the 2nd fraction, since 21 × 30 = 630,
81/21 = 81 × 30/21 × 30 = 2430/630 - Since the denominators are now the same, the fraction with the bigger numerator is the greater fraction
- 63/630 < 2430/630 or 9/90 < 81/21
MathStep (Works offline)
Download our mobile app and learn to work with fractions in your own time:
Android and iPhone/ iPad
Related: 18/90 and 81/21 9/90 and 81/42 27/90 and 81/21 9/90 and 81/63 45/90 and 81/21 63/90 and 81/21