# Recent content by rooski

1. ### Probability Theory - Expectation Problem

But if it tells me that it only takes on positive integers then technically it can take on infinite positive integers right? And from what i gather you need to know the range of x in order to calculate the expectations. :S
2. ### Probability - Poisson Random Variable

Ok i figured out the first part of the question - the probability of the trials having more than 1 success im 36 trials is 0.2642 using the binomial distribution function. How do i apply the poisson variable to this?
3. ### Probability - Poisson Random Variable

So the number of trials, n, is 36 and the probability of success, p, is 1/36, right?
4. ### Probability - Poisson Random Variable

Homework Statement A trial consists of tossing two dice. The result is counted as successful if the sum of the outcomes is 12. What is the probability that the number of successes in 36 such trials is greater than one? What is this probability if we approximate its value using the Poisson...
5. ### Probability Theory - Expectation Problem

Homework Statement Discrete random variables X and Y , whose values are positive integers, have the joint probability mass function , (, ) = 2−−. Determine the marginal probability mass functions () and (). Are X and Y independent? Determine [], [ ], and [ ]. The Attempt at a Solution...
6. ### Conditional Probability

Homework Statement The old TV game Let’s Make a Deal hosted by Monty Hall could be summarized as follows. Suppose you are on a game show, and you are given the choice of three doors. Behind one door is a car, behind the others, goats. You pick a door, say number 1, and the host, who knows...
7. ### Probability Question

P(L) = 0 * 1/3 + 1 * 1/3 + ½ * 1/3 = 3/6 = 1/2 So there is a 50% chance that we will end up with the lowest card if we reject the first random card.
8. ### Probability Question

P(L|B) = 1 since you will reject 3 if it appears, or accept 1 when it appears. P(L|C) = 1/2 since you will accept 2 if it appears or accept 1 when it appears. Have i calculated P(A) P(B) and P(C) wrong?
9. ### Probability Question

Assuming L is the event i accept the lowest card, P(L) = P(L|A)P(A) + P(L|B)P(B) + P(L|C)P(C) Where A,B,C denote cards 1,2,3 respectively. Is that right or am i off? It seems wring since P(A), P(B) and P(C) would all be 1/3.
10. ### Probability Question

Ah right, dunno how i missed that. So how do i calculate the chance that the second card will be lower? I have 0, 1 and 1/2 as the probabilities, depending on which card is rejected first.
11. ### Probability Question

Homework Statement Suppose that the integer values 1 2 and 3 are written on each of three different cards. Suppose you do not know which number is the lowest (you do not know beforehand what the values on the cards are). Suppose that you are to be offered these cards in a random order. When...
12. ### Combination + Permutation Question

The instructions given are pretty vague, i will admit. I doubt the teacher wants us to get too involved with the semantics of the question. Since the other team has not been mentioned I will simply assume that i am not supposed to factor in the other team's score at all. That said, I think...
13. ### Combination + Permutation Question

I assume for B) that they are trying to keep it simple. There are 5 players taking shots on the net. If 2 players score then no more kicks are taken. I think i did this wrong. We don't want factorials, we want combinations. There is a possibility of 5C2 + 5C3 + 5C4 + 5C5 combinations of players...
14. ### Combination + Permutation Question

Homework Statement Consider a team of 11 soccer players, all of whom are equally good players and can play any position. (a) Suppose that the team has just finished regulation time for a play-off game and the score is tied with the other team. The coach has to select five players for...
15. ### Induction - Fibonacci Numbers

Homework Statement use induction to prove (my formatting is off sorry) \overline{n} \sum \underline{k=1} f _{2k-1} = f_{2n} The Attempt at a Solution To start we need to show that f3 is valid. So we show that f2 + f1 = f3, which is the case. The next part is the confusing part for me. Do...