Compare 12/40 and 45/21
1st number: 12/40, 2nd number: 2 3/21
12/40 is smaller than 45/21
Steps for comparing fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 40 and 21 is 840
Next, find the equivalent fraction of both fractional numbers with denominator 840 - For the 1st fraction, since 40 × 21 = 840,
12/40 = 12 × 21/40 × 21 = 252/840 - Likewise, for the 2nd fraction, since 21 × 40 = 840,
45/21 = 45 × 40/21 × 40 = 1800/840 - Since the denominators are now the same, the fraction with the bigger numerator is the greater fraction
- 252/840 < 1800/840 or 12/40 < 45/21
MathStep (Works offline)
Download our mobile app and learn to work with fractions in your own time:
Android and iPhone/ iPad
Related: 24/40 and 45/21 12/40 and 90/21 12/80 and 45/21 12/40 and 45/42 36/40 and 45/21 12/40 and 45/63 60/40 and 45/21 84/40 and 45/21