SOLUTION: 1. In how many ways can the letters of the word POLICEMAN be arranged if the "word" must begin with L and end with a vowel? 2. What is the probability that if the letters of POL

Algebra ->  Permutations -> SOLUTION: 1. In how many ways can the letters of the word POLICEMAN be arranged if the "word" must begin with L and end with a vowel? 2. What is the probability that if the letters of POL      Log On


   



Question 979205: 1. In how many ways can the letters of the word POLICEMAN be arranged if the "word" must begin with L and end with a vowel?
2. What is the probability that if the letters of POLICEMAN are randomly placed in a row, the "word" will begin with L and end with a vowel?

Answer by Edwin McCravy(20055) About Me  (Show Source):
You can put this solution on YOUR website!
1. In how many ways can the letters of the word POLICEMAN
be arranged if the "word" must begin with L and end with a vowel?
There is 1 way to choose the 1st letter as L.
There are 4 ways to choose the last letter as a vowel.
There are 7! ways to choose the letters in between.

That's 1*4*7! = 20160 ways.

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2. What is the probability that if the letters of POLICEMAN
are randomly placed in a row, the "word" will begin with L and end with a vowel?
20160 ways out of 9! or 20160%2F362880%22%22=%22%221%2F18

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You can also do the second part without using the first part at all.

The probability of choosing a P first is 1/9.
The probability of then choosing a vowel last in 1/2.  [Because when you've
chosen an L first there are 8 letters left, half vowels and half consonants.

So that probability is (1/9)(1/2) = 1/18.  (This way you can ignore the
letters in between the first and last.)

Edwin