Answers

Compare 18/7 and 21/81

1^st number: 2 4/7, 2^nd number: 21/81

18/7 is greater than 21/81

Steps for comparing fractions

1. Find the least common denominator or LCM of the two denominators:
   LCM of 7 and 81 is 567
   
   Next, find the equivalent fraction of both fractional numbers with denominator 567
2. For the 1st fraction, since 7 × 81 = 567,
   18/7 = 18 × 81/7 × 81 = 1458/567
3. Likewise, for the 2nd fraction, since 81 × 7 = 567,
   21/81 = 21 × 7/81 × 7 = 147/567
4. Since the denominators are now the same, the fraction with the bigger numerator is the greater fraction
5. 1458/567 > 147/567 or 18/7 > 21/81

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