## Probability word begins with O, ends with R

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Mere
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### Probability word begins with O, ends with R

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"?

stapel_eliz
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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.

Mere
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Joined: Fri Aug 07, 2009 3:01 am
Location: USA
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### Re: Probability word begins with O, ends with R

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?

stapel_eliz
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...would it be 6/120?
Your reasoning looks good to me!