Compare 21/45 and 10/18
21/45 is smaller than 10/18
Steps for comparing fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 45 and 18 is 90
Next, find the equivalent fraction of both fractional numbers with denominator 90 - For the 1st fraction, since 45 × 2 = 90,
21/45 = 21 × 2/45 × 2 = 42/90 - Likewise, for the 2nd fraction, since 18 × 5 = 90,
10/18 = 10 × 5/18 × 5 = 50/90 - Since the denominators are now the same, the fraction with the bigger numerator is the greater fraction
- 42/90 < 50/90 or 21/45 < 10/18
MathStep (Works offline)
Download our mobile app and learn to work with fractions in your own time:
Android and iPhone/ iPad
Related: 42/45 and 10/18 21/45 and 20/18 21/90 and 10/18 21/45 and 10/36 63/45 and 10/18 21/45 and 30/18 21/45 and 10/54 21/45 and 50/18 21/45 and 10/90 21/45 and 70/18