Compare 20/45 and 5/21
20/45 is greater than 5/21
Steps for comparing fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 45 and 21 is 315
Next, find the equivalent fraction of both fractional numbers with denominator 315 - For the 1st fraction, since 45 × 7 = 315,
20/45 = 20 × 7/45 × 7 = 140/315 - Likewise, for the 2nd fraction, since 21 × 15 = 315,
5/21 = 5 × 15/21 × 15 = 75/315 - Since the denominators are now the same, the fraction with the bigger numerator is the greater fraction
- 140/315 > 75/315 or 20/45 > 5/21
MathStep (Works offline)
Download our mobile app and learn to work with fractions in your own time:
Android and iPhone/ iPad
Related: 40/45 and 5/21 20/45 and 10/21 20/90 and 5/21 20/45 and 5/42 60/45 and 5/21 20/45 and 15/21 20/45 and 5/63 20/45 and 25/21 20/45 and 35/21