Halloween is for Brain Teasers and Paradoxes

In the last few weeks quite a few people have done postings on brain teasers so I thought I would post a bunch of them here.

IQ Test --Solve it-" Pure Logic test from Harvard University If: 1 = 5, 2 = 25, 3 = 325, 4 = 4325, 5 = ?

(Thanks Vijay Kumar)


If you choose an answer to this question at random, what is the chance you will be correct?
A) 25%
B) 50%
C) 60%
D) 25%


(Thanks Nathan of Flowing Data)


If you have three light switches in one room that each turn on one lamp in another room, and you can only enter the room with the lamps once how do you determine which switch goes to which lamp?


Good video on the Monte Hall Problem ( although I would stay with the first door because I already have a car, but I could use a goat)

Finally here is a cool website of Riddles and Brain Teasers 

If you have any other ones that you like send them to me and I will add them.