Compare 21/30 and 15/8
1st number: 21/30, 2nd number: 1 7/8
21/30 is smaller than 15/8
Steps for comparing fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 30 and 8 is 120
Next, find the equivalent fraction of both fractional numbers with denominator 120 - For the 1st fraction, since 30 × 4 = 120,
21/30 = 21 × 4/30 × 4 = 84/120 - Likewise, for the 2nd fraction, since 8 × 15 = 120,
15/8 = 15 × 15/8 × 15 = 225/120 - Since the denominators are now the same, the fraction with the bigger numerator is the greater fraction
- 84/120 < 225/120 or 21/30 < 15/8
MathStep (Works offline)
Download our mobile app and learn to work with fractions in your own time:
Android and iPhone/ iPad
Related: 42/30 and 15/8 21/30 and 30/8 21/60 and 15/8 21/30 and 15/16 63/30 and 15/8 21/30 and 45/8 21/90 and 15/8 21/30 and 15/24 21/30 and 75/8 21/30 and 15/40 21/30 and 15/56