Compare 20/81 and 21/90
20/81 is greater than 21/90
Steps for comparing fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 81 and 90 is 810
Next, find the equivalent fraction of both fractional numbers with denominator 810 - For the 1st fraction, since 81 × 10 = 810,
20/81 = 20 × 10/81 × 10 = 200/810 - Likewise, for the 2nd fraction, since 90 × 9 = 810,
21/90 = 21 × 9/90 × 9 = 189/810 - Since the denominators are now the same, the fraction with the bigger numerator is the greater fraction
- 200/810 > 189/810 or 20/81 > 21/90
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