Compare 21/15 and 70/21
1st number: 1 6/15, 2nd number: 3 7/21
21/15 is smaller than 70/21
Steps for comparing fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 15 and 21 is 105
Next, find the equivalent fraction of both fractional numbers with denominator 105 - For the 1st fraction, since 15 × 7 = 105,
21/15 = 21 × 7/15 × 7 = 147/105 - Likewise, for the 2nd fraction, since 21 × 5 = 105,
70/21 = 70 × 5/21 × 5 = 350/105 - Since the denominators are now the same, the fraction with the bigger numerator is the greater fraction
- 147/105 < 350/105 or 21/15 < 70/21
MathStep (Works offline)
Download our mobile app and learn to work with fractions in your own time:
Android and iPhone/ iPad
Related: 42/15 and 70/21 21/30 and 70/21 21/15 and 70/42 63/15 and 70/21 21/45 and 70/21 21/15 and 70/63 21/75 and 70/21