Thursday, October 11, 2007

Going to the Show?

A theater has five entrances. In how many ways can you enter and leave by a different entrance?


  1. Mmmm...combinations and permutations...

    5 entrance choices, 4 exit choices per entrance choice. 5 times 4 = 20 ways.

    Or, since you have a group of five, and you're choosing 2, and order DOES matter, you use the permutations formula:

    nPr = n!/(n-r)! = 5!/3! = 20

  2. you could go in and out the same way...?

  3. actually, nick, the question specifies "by a different entrance"...

  4. Looks like Abe covered it all. 20 is the answer.


Leave your answer or, if you want to post a question of your own, send me an e-mail. Look in the about section to find my e-mail address. If it's new, I'll post it soon.

Please don't leave spam or 'Awesome blog, come visit mine' messages. I'll delete them soon after.

Enter your Email and join hundreds of others who get their Question of the Day sent right to their mailbox

Preview | Powered by FeedBlitz

The Lamplight Manor Puzz 3-D
Are you looking for a particular puzzle, riddle, question, etc? Or do you want to find the answer today rather than wait till tomorrow!