Probability word begins with O, ends with R  TOPIC_SOLVED

Sequences, counting (including probability), logic and truth tables, algorithms, number theory, set theory, etc.

Probability word begins with O, ends with R

Postby Mere on Sat Aug 08, 2009 12:50 am

Can someone show me how to do this problem? I think that it is conditional probability, but I am unsure how to set up the problem. Thanks...

If the letters in the word "POKER" are rearranged, what is the probability that the word will begin with the letter "O" and end with the letter "R"?
Mere
 
Posts: 7
Joined: Fri Aug 07, 2009 3:01 am
Location: USA

Sponsor

Sponsor
 

  TOPIC_SOLVED

Postby stapel_eliz on Sat Aug 08, 2009 1:17 am

In how many ways can you arrange the letters?

If you fix O as the first letter and R as the last, in how many ways can you arrange the other letters?

Divide the latter by the former. :wink:
User avatar
stapel_eliz
 
Posts: 1714
Joined: Mon Dec 08, 2008 4:22 pm

Re: Probability word begins with O, ends with R

Postby Mere on Sat Aug 08, 2009 1:29 am

So...

If you can arrange all of the letters in "POKER" in 120 ways, and
you can arrange letters "PKE" (with O and R on the outside) in 6 ways,
would it be 6/120?
Mere
 
Posts: 7
Joined: Fri Aug 07, 2009 3:01 am
Location: USA

Postby stapel_eliz on Sat Aug 08, 2009 2:01 am

Mere wrote:...would it be 6/120?

Your reasoning looks good to me! :D

Just remember to simplify your answer before you hand it in. :wink:
User avatar
stapel_eliz
 
Posts: 1714
Joined: Mon Dec 08, 2008 4:22 pm


Return to Discrete Math