Compare 42/30 and 72/21
1st number: 1 12/30, 2nd number: 3 9/21
42/30 is smaller than 72/21
Steps for comparing fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 30 and 21 is 210
Next, find the equivalent fraction of both fractional numbers with denominator 210 - For the 1st fraction, since 30 × 7 = 210,
42/30 = 42 × 7/30 × 7 = 294/210 - Likewise, for the 2nd fraction, since 21 × 10 = 210,
72/21 = 72 × 10/21 × 10 = 720/210 - Since the denominators are now the same, the fraction with the bigger numerator is the greater fraction
- 294/210 < 720/210 or 42/30 < 72/21
MathStep (Works offline)
Download our mobile app and learn to work with fractions in your own time:
Android and iPhone/ iPad
Related: 84/30 and 72/21 42/60 and 72/21 42/30 and 72/42 42/90 and 72/21 42/30 and 72/63