Answers

Compare 30/75 and 21/81

30/75 is greater than 21/81

Steps for comparing fractions

1. Find the least common denominator or LCM of the two denominators:
   LCM of 75 and 81 is 2025
   
   Next, find the equivalent fraction of both fractional numbers with denominator 2025
2. For the 1st fraction, since 75 × 27 = 2025,
   30/75 = 30 × 27/75 × 27 = 810/2025
3. Likewise, for the 2nd fraction, since 81 × 25 = 2025,
   21/81 = 21 × 25/81 × 25 = 525/2025
4. Since the denominators are now the same, the fraction with the bigger numerator is the greater fraction
5. 810/2025 > 525/2025 or 30/75 > 21/81

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