Compare 15/21 and 12/90
15/21 is greater than 12/90
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,
15/21 = 15 × 30/21 × 30 = 450/630 - Likewise, for the 2nd fraction, since 90 × 7 = 630,
12/90 = 12 × 7/90 × 7 = 84/630 - Since the denominators are now the same, the fraction with the bigger numerator is the greater fraction
- 450/630 > 84/630 or 15/21 > 12/90
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