Compare 15/30 and 21/84
15/30 is greater than 21/84
Steps for comparing fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 30 and 84 is 420
Next, find the equivalent fraction of both fractional numbers with denominator 420 - For the 1st fraction, since 30 × 14 = 420,
15/30 = 15 × 14/30 × 14 = 210/420 - Likewise, for the 2nd fraction, since 84 × 5 = 420,
21/84 = 21 × 5/84 × 5 = 105/420 - Since the denominators are now the same, the fraction with the bigger numerator is the greater fraction
- 210/420 > 105/420 or 15/30 > 21/84
MathStep (Works offline)
Download our mobile app and learn to work with fractions in your own time:
Android and iPhone/ iPad
Related: 15/30 and 42/84 15/60 and 21/84 45/30 and 21/84 15/30 and 63/84 15/90 and 21/84 75/30 and 21/84