Compare 1/90 and 1/21
1/90 is smaller than 1/21
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,
1/90 = 1 × 7/90 × 7 = 7/630 - Likewise, for the 2nd fraction, since 21 × 30 = 630,
1/21 = 1 × 30/21 × 30 = 30/630 - Since the denominators are now the same, the fraction with the bigger numerator is the greater fraction
- 7/630 < 30/630 or 1/90 < 1/21
MathStep (Works offline)
Download our mobile app and learn to work with fractions in your own time:
Android and iPhone/ iPad
Related: 2/90 and 1/21 1/90 and 2/21 1/90 and 1/42 3/90 and 1/21 1/90 and 3/21 1/90 and 1/63 5/90 and 1/21 1/90 and 5/21 7/90 and 1/21 1/90 and 7/21