12 Balls, 1 slightly heavier

I got asked this question at least in 3 different job interviews!  What's the point?  What are they "looking" for?

At least the next 2 times, I already had the answer and just spewed it out.

The question:

You have 12 identical balls but one slightly heavier.  You also have a balance scale.  How would you isolate the slightly heavier ball using the balance scale as little as possible?

Answer:

Divide the balls into 2 groups of 6.  Use the balance scale to find the slightly heavier group and discard the lighter one.  Then divide the remaining 6 into 2 groups of 3 and weight on the scale.  Discard the lighter 3 balls.  Now take 2 of the remaining 3 balls and compare them on the scale.  If they weight the same, then the left over one is heavier.  If there's a difference, then take the heavier one on the scale.

I've actually seen this in a job interview:

How do you put a giraffe into the refrigerator?
Correct answer: Open the refrigerator door, put the giraffe in, and close the door. This question tests whether or not the candidate is doing simple things in a complicated way.

How do you put an elephant in the refrigerator?
Incorrect answer: Open the refrigerator door, put in the elephant, and close the door. Correct answer: Open the refrigerator door, take out the giraffe, put in the elephant, and close the door. This question tests your foresight.

The Lion King is hosting an animal conference. All the animals in the world attend except one. Which animal does not attend?
Correct answer: The elephant. The elephant is in the refrigerator, remember? This tests if you are capable of comprehensive thinking.

There is a river notoriously known for it’s large crocodile population. With ease, how do you safely cross it?
Correct answer: Simply swim across. All of the crocodiles are attending the Lion King’s animal conference. This questions your reasoning ability.