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#1 Help Me ! » Set Theory » 2012-05-08 11:15:09
- chineseballer06
- Replies: 11
jkhkj
#2 Re: Help Me ! » Roulette Probability » 2011-03-31 08:30:30
Okay thanks everyone!! That really helped! 
#3 Re: Help Me ! » Roulette Probability » 2011-03-31 05:12:28
Hi bobbym
What distribution did you use to get that? I don't know if this helps but in class we are learning about discrete distributions like Poisson, Bernouilli, and geometric distributions.
#4 Help Me ! » Roulette Probability » 2011-03-30 15:23:17
- chineseballer06
- Replies: 25
Hi everyone, I am having difficulty with this problem any help is greatly appreciated.
In European roulette the ball lads on one of the numbers 0,1,...,36 in every spin of the wheel. A gambler offers at even odds the bet that the house number 0 will come up once in every 25 spins of the wheel. What is the gambler's expected profit per dollar bet?
If you can help me figure out which distribution to use that would help a lot, thanks again!
#5 Re: Help Me ! » Expectation of the word Mississippi » 2011-03-04 15:06:45
oh okay that makes sense, and no I don't, im thinking about taking some computer science classes though
#6 Re: Help Me ! » Expectation of the word Mississippi » 2011-03-04 05:20:03
Also is there a way I can learn about these simulations your talking about?
#7 Re: Help Me ! » Expectation of the word Mississippi » 2011-03-04 05:12:46
Hi bobbym,
Thank you for the help.
I have a question though, where do u get the multiple of 10 in your solution?
#8 Re: Help Me ! » Expectation of the word Mississippi » 2011-03-03 19:46:05
Its a school problem
#9 Re: Help Me ! » Expectation of the word Mississippi » 2011-03-03 19:29:10
Oh I see that is very interesting.
#10 Re: Help Me ! » Expectation of the word Mississippi » 2011-03-03 19:16:28
Oh okay do you have a program that can do that or something?
#11 Re: Help Me ! » Expectation of the word Mississippi » 2011-03-03 19:06:15
Hi bobbym,
How did you get that?
#12 Help Me ! » Expectation of the word Mississippi » 2011-03-03 14:11:47
- chineseballer06
- Replies: 19
What is the expected value of the number of times that two adjacent letters are the same in a random permutation of the word Mississippi?
I was wondering if someone could help me determine if I got this problem right.
So I let the random variable Xi=1 if there are two adjacent letters that are the same and =0 otherwise.
I said i=0,...,7 because there can only be a maximum of 7 times where two adjacent letters are the same.
Ways to arrange Mississippi = 11!/(4!4!2!)=34,650
Ways to arrange Mississippi where there are no adjacent letters that are the same =34,650-4!4!4!2!=7002
P(Xi=0)=(7002/34650)
P(Xi=1)=(27648/34650)
Expected value of the number of times that two adjacent letters are similar in a random permutation
=E(X0+X1+,...,+X7)
=7(P(Xi=1))=7(27648/34650)
=5.585...
Any help is greatly appreciated!
#13 Re: Help Me ! » Expected Value » 2011-03-03 12:06:03
Yeah I think I can handle it! Thank you so much bobbym that helped a ton!!! I don't get why my teacher assigned that problem lol the whole class was asking questions about it, but it makes a lot more sense now.
#14 Re: Help Me ! » Expected Value » 2011-03-01 18:24:13
Yeah I don't know that's why I was so confused with this problem. He introduced us to a little bit of Euler Maclaurin Summation formulas but thats about it.
#15 Re: Help Me ! » Expected Value » 2011-03-01 17:37:37
Okay everything is making sense to me except how do you go from the part in the equation with the summation to just having n's?
#16 Re: Help Me ! » Expected Value » 2011-02-27 16:13:11
Oh okay thanks for the help I don't know how I would have gotten that by myself. Do you know how I would do this for the second part?
#17 Help Me ! » Expected Value » 2011-02-26 16:11:27
- chineseballer06
- Replies: 9
Hey everyone, I am struggling with this problems and would appreciate some help!
The question is:
Calculate the expected value of the greater of two numbers when two different numbers are picked at random from the numbers 1,...,n. What is the expected value of the absolute difference between the two numbers?
Thanks!!
#18 Re: Help Me ! » Probability: Conditional and Bayes » 2011-02-16 16:03:21
Yeah that does help to see it, and thanks for the conditional probability example! I appreciate the help everyone!!
#19 Re: Help Me ! » Probability: Conditional and Bayes » 2011-02-16 12:21:07
Oh okay!! Thanks that makes a lot of sense. Just curious, do you know how to do this using the conditional probability formula or Bayes' Formula?
#20 Re: Help Me ! » Probability: Conditional and Bayes » 2011-02-16 05:31:51
Hi bobbym and gAr,
How did you find P(Wreck not being found in the area) ?
#21 Help Me ! » Probability: Conditional and Bayes » 2011-02-15 18:18:21
- chineseballer06
- Replies: 12
Hi everyone, I need some help with a couple problems and appreciate any help that I can get.
The first problem is: "A die is rolled to yield a number between 1 and 6, and then a coin is tossed that many times. What is the probability that heads will not appear?
The answer I got is 1/6(.5+.5^2+.5^3+.5^4+.5^5+.5^6) but I don't know if that is the right way to go about it.
The second problem I am just completely lost and its: "It is believed that a sought-after wreck will be in a certain sea area with probability p = 0.4. A search in that area will detect the wreck with probability d = 0.9 if it is there. What is the revised probability of the wreck being in the area when the area is searched and no wreck is found?
Any help is greatly appreciated!
#22 Re: Help Me ! » Probability » 2011-02-05 16:49:35
Got it!
Thanks everyone!
#23 Re: Help Me ! » Probability » 2011-02-05 15:25:27
Hi bobbym,
Its still not working for some reason, it says the page has been removed. And I've already learned it thats just the topic we finished in class so that is probably how my professor wants me to solve this problem
#24 Re: Help Me ! » Probability » 2011-02-05 13:06:59
That link that you sent in box #7 doesn't seem to be working for me
#25 Re: Help Me ! » Probability » 2011-02-05 13:03:32
Sorry Bobbym,
I'm a little confused about how to use the inclusion exclusion principle. What are my 3 events that I am taking the union of?