Compare 9/21 and 84/90
9/21 is smaller than 84/90
Steps for comparing fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 21 and 90 is 630
Next, find the equivalent fraction of both fractional numbers with denominator 630 - For the 1st fraction, since 21 × 30 = 630,
9/21 = 9 × 30/21 × 30 = 270/630 - Likewise, for the 2nd fraction, since 90 × 7 = 630,
84/90 = 84 × 7/90 × 7 = 588/630 - Since the denominators are now the same, the fraction with the bigger numerator is the greater fraction
- 270/630 < 588/630 or 9/21 < 84/90
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