Compare 3/21 and 7/9
3/21 is smaller than 7/9
Steps for comparing fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 21 and 9 is 63
Next, find the equivalent fraction of both fractional numbers with denominator 63 - For the 1st fraction, since 21 × 3 = 63,
3/21 = 3 × 3/21 × 3 = 9/63 - Likewise, for the 2nd fraction, since 9 × 7 = 63,
7/9 = 7 × 7/9 × 7 = 49/63 - Since the denominators are now the same, the fraction with the bigger numerator is the greater fraction
- 9/63 < 49/63 or 3/21 < 7/9
MathStep (Works offline)
Download our mobile app and learn to work with fractions in your own time:
Android and iPhone/ iPad
Related: 6/21 and 7/9 3/21 and 14/9 3/42 and 7/9 3/21 and 7/18 9/21 and 7/9 3/21 and 21/9 3/63 and 7/9 3/21 and 7/27 15/21 and 7/9 3/21 and 35/9 3/21 and 7/45 3/21 and 49/9 3/21 and 7/63