Compare 72/21 and 45/40
1st number: 3 9/21, 2nd number: 1 5/40
72/21 is greater than 45/40
Steps for comparing fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 21 and 40 is 840
Next, find the equivalent fraction of both fractional numbers with denominator 840 - For the 1st fraction, since 21 × 40 = 840,
72/21 = 72 × 40/21 × 40 = 2880/840 - Likewise, for the 2nd fraction, since 40 × 21 = 840,
45/40 = 45 × 21/40 × 21 = 945/840 - Since the denominators are now the same, the fraction with the bigger numerator is the greater fraction
- 2880/840 > 945/840 or 72/21 > 45/40
MathStep (Works offline)
Download our mobile app and learn to work with fractions in your own time:
Android and iPhone/ iPad
Related: 72/21 and 90/40 72/42 and 45/40 72/21 and 45/80 72/63 and 45/40