Exactly 5/6 of the cows on a certain farm have cow bells

Exactly 5/6 of the cows on a certain farm have cow bells. If exactly half of the cows with bells are
brown, what is the minimum possible number of cows on the ranch?

A. 6
B. 8
C. 12
D. 18
E. 24

Answer: The trick to this question is that the number of cows cannot be fractional; it must be an integer.

The number of brown cows is: (1/2) × (5/6) × the number of cows.

12 is the smallest positive integer that yields another integer when multiplied by 5/12, so it is the minimum possible number of cows.

Correct Answer: Choice C

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