Puzzle Questions

Puzzle questions during an interview I had an interview yesterday. The gentleman that interviewed me said, "I'm sorry....I don't have your information in front of me, I assume you are applying for an IT Job." I answered, "yes." He said, "well, close your computer down and don't cheat." I did what he asked. I was intrigued. He said, "You have 9 marbles; 8 weigh exactly the same, and one weighs a bit more. You also have a balance scale. How would you go about finding out how to determine which marble weighed more than the 8 others?"

I proceeded to tell him that there are a number of ways one can do that.

  • first, you can weigh two at a time.

  • He said, "that takes to long. Isn't there an easier way?"

  • I said, "yes! One can put 4 marbles on each scale and keep one marble off, and I might get lucky."

  • "if not, I will know immediately which side weighed more."

  • "then, I could........

He stopped me and said, "you seem like you are struggling. We are looking for people that don't struggle." He then said, "you are not the person we are looking for."

I have a problem with this. One never "shoots from the hip." One analyzes the strategies and actually gets more than a minute to do so; then one figures out the best possible strategy."


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