Compare 21/90 and 12/81
21/90 is greater than 12/81
Steps for comparing fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 90 and 81 is 810
Next, find the equivalent fraction of both fractional numbers with denominator 810 - For the 1st fraction, since 90 × 9 = 810,
21/90 = 21 × 9/90 × 9 = 189/810 - Likewise, for the 2nd fraction, since 81 × 10 = 810,
12/81 = 12 × 10/81 × 10 = 120/810 - Since the denominators are now the same, the fraction with the bigger numerator is the greater fraction
- 189/810 > 120/810 or 21/90 > 12/81
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