Compare 4/90 and 12/21
4/90 is smaller than 12/21
Steps for comparing fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 90 and 21 is 630
Next, find the equivalent fraction of both fractional numbers with denominator 630 - For the 1st fraction, since 90 × 7 = 630,
4/90 = 4 × 7/90 × 7 = 28/630 - Likewise, for the 2nd fraction, since 21 × 30 = 630,
12/21 = 12 × 30/21 × 30 = 360/630 - Since the denominators are now the same, the fraction with the bigger numerator is the greater fraction
- 28/630 < 360/630 or 4/90 < 12/21
MathStep (Works offline)
Download our mobile app and learn to work with fractions in your own time:
Android and iPhone/ iPad
Related: 8/90 and 12/21 4/90 and 24/21 4/90 and 12/42 12/90 and 12/21 4/90 and 36/21 4/90 and 12/63 20/90 and 12/21 4/90 and 60/21 28/90 and 12/21 4/90 and 84/21