# Math Help - Probabilities Concerning 3-Letter Sequences

1. ## Probabilities Concerning 3-Letter Sequences

1)We construct a 3-letter sequence by randomly choosing the letters A and B with probabilities 2/3 and 1/3 ,respectively

a)What is the probability that we get one of ABB or ABA?

b)What is the probability that the second letter is B?

c)Suppose we win as many TL's as the number of A 's in the word (i.e 1 TL if there is one A, 2 TL if 2 A's, 3 TL if 3 A's).What is the expectation of the money we win?

d)What is the expected number of A's in the word?

Thank you so much

2. Originally Posted by berkan
1)We construct a 3-letter sequence by randomly choosing the letters A and B with probabilities 2/3 and 1/3 ,respectively

a)What is the probability that we get one of ABB or ABA?

b)What is the probability that the second letter is B?

c)Suppose we win as many TL's as the number of A 's in the word (i.e 1 TL if there is one A, 2 TL if 2 A's, 3 TL if 3 A's).What is the expectation of the money we win?

d)What is the expected number of A's in the word?
You should understand that this is not a homework service nor is it a tutorial service. Please either post some of your own work on these problems or explain what you do not understand about the question. Moreover, we discourage posting a whole list of problems at one time, especially if you show no effort.

3. Hi sir

I cant do anything because of this I wrote these questions. I dont understand anything so what can I do?

4. Originally Posted by berkan
I cant do anything because of this I wrote these questions. I dont understand anything so what can I do?
This is not a homework service nor is it a tutorial service.
So you need a sit-down, one on one discussion with you tutor.