Compare 10/18 and 20/21
10/18 is smaller than 20/21
Steps for comparing fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 18 and 21 is 126
Next, find the equivalent fraction of both fractional numbers with denominator 126 - For the 1st fraction, since 18 × 7 = 126,
10/18 = 10 × 7/18 × 7 = 70/126 - Likewise, for the 2nd fraction, since 21 × 6 = 126,
20/21 = 20 × 6/21 × 6 = 120/126 - Since the denominators are now the same, the fraction with the bigger numerator is the greater fraction
- 70/126 < 120/126 or 10/18 < 20/21
MathStep (Works offline)
Download our mobile app and learn to work with fractions in your own time:
Android and iPhone/ iPad
Related: 20/18 and 20/21 10/18 and 40/21 10/36 and 20/21 10/18 and 20/42 30/18 and 20/21 10/18 and 60/21 10/54 and 20/21 10/18 and 20/63 50/18 and 20/21 10/90 and 20/21 70/18 and 20/21