Compare 21/70 and 20/30
21/70 is smaller than 20/30
Steps for comparing fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 70 and 30 is 210
Next, find the equivalent fraction of both fractional numbers with denominator 210 - For the 1st fraction, since 70 × 3 = 210,
21/70 = 21 × 3/70 × 3 = 63/210 - Likewise, for the 2nd fraction, since 30 × 7 = 210,
20/30 = 20 × 7/30 × 7 = 140/210 - Since the denominators are now the same, the fraction with the bigger numerator is the greater fraction
- 63/210 < 140/210 or 21/70 < 20/30
MathStep (Works offline)
Download our mobile app and learn to work with fractions in your own time:
Android and iPhone/ iPad
Related: 42/70 and 20/30 21/70 and 40/30 21/70 and 20/60 63/70 and 20/30 21/70 and 60/30 21/70 and 20/90