Compare 10/21 and 42/45
10/21 is smaller than 42/45
Steps for comparing fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 21 and 45 is 315
Next, find the equivalent fraction of both fractional numbers with denominator 315 - For the 1st fraction, since 21 × 15 = 315,
10/21 = 10 × 15/21 × 15 = 150/315 - Likewise, for the 2nd fraction, since 45 × 7 = 315,
42/45 = 42 × 7/45 × 7 = 294/315 - Since the denominators are now the same, the fraction with the bigger numerator is the greater fraction
- 150/315 < 294/315 or 10/21 < 42/45
MathStep (Works offline)
Download our mobile app and learn to work with fractions in your own time:
Android and iPhone/ iPad
Related: 20/21 and 42/45 10/21 and 84/45 10/42 and 42/45 10/21 and 42/90 30/21 and 42/45 10/63 and 42/45 50/21 and 42/45 70/21 and 42/45