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A letter lock consists of three rings each marked with six different letters. The number of distinct unsuccessful attempts to open the lock is at the most__________?

Correct answer: C. 215

  • A. 216
  • B. 243
  • C. 215
  • D. 729Downloading Interactive Party Trivia Games

Explanation

Each of the three rings has 6 choices, so the lock has 6 x 6 x 6 = 216 total combinations. If exactly one combination opens the lock, the maximum number of unsuccessful attempts is 216 - 1 = 215 attempts. The likely trap is option a, 216, which counts all combinations but includes the successful one.

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