>I will shortly start looking for a new employee (permanent or contract). Does anyone have any good IQ type questions or good interview type questions? If anyone knows of any good websites with this kind of information that would be appreciated also.
>I like to use some IQ type questions in the phone interview just to find out if it is worth bringing the person in for a face to face interview. Questions does not have to be directly computer related and should be able to be answered within 30 seconds without the use of pen and paper. More difficult questions are also welcome.
>
>I am tempted to sneak in a Microsoft question, like : how many cars are there in Los Angeles? Where the object is not to get the correct answer but to use some kind of logic to derive an answer and not just answer I don't know. Has anyone tried that approach?
>
>Thanks,
>Einar

Some "mathematical games" are quite simple, but it is surprising how many people get them wrong. For example, the riddle with the fast-growing plant:

A water plant grows so fast that every day it covers twice the surface it covered the previous day. 15 days after planting it in a pond, it covers half the surface. When does it cover the entire pond surface?

It is surprising how many people answer "on day 30", when the correct answer seems so obvious. - Well, in any case, I would allow a little more than 30 seconds to think about that one.

Others (mathematical games) are actually quite difficult, and perhaps more adequate for having fun than to measure intelligence.

Here are a few that are confusing at first, but can be figured out without advanced math, etc., just with logic:

What's twice the half of two and a half?


A man stands in front of a picture and says:

Brothers and sisters have I none,
but this boy's father is my father's son.

Who is the man in the picture?



The last one may be too confusing for most people.


Here is one (quite tricky) where the person has to think about the general situation (you may want to change the units involved):

A man paints the outer walls of a boat. He stands on a hanging ladder; the lowest rung - where he is standing - is 10 cm. from the surface of the water; there are rungs every 30 cm. If the high tide makes the water rise half a meter, how many rungs does he have to climb so as not to get his feet wet?

(No, the answer is not 2 - see footnote 1)

However, around 80% of the people I asked this question can't even do the calculations to get this result. So, a few questions that involve simple problem-solving skills may be in order. A lot of people might answer correctly if you tell them to multiply 20 * 5, but will get confused if you ask them to do an area calculation involving these numbers - especially if they have to calculate backwards: A certain rectangular piece of garden has 100 square feet. One of its sides is 5 feet. How long is the longer side? Even without advanced algebra knowledge, it should be quite clear that you have to divide here, instead of multiplying. - By the way, the water plant can be stated "backwards" as: "On day 16, it covers the entire surface. When does it cover half the surface?"


(1) Hint: Remember where he is located.