# probability homework help

1. ### Probability of developing a lung cancer disease

I need to solve this problem: A cohort study is done to assess the impact of smoking on lung cancer. In this study, a large representative sample of first year university students are followed for 40 years. For each student, the smoking status is recorded as well as the lung cancer status at...
2. ### Homework help, want to check my method for probability and hypothesis test

I would be most obliged if someone would look at my solution and advise if my method and answers are correct. Mean lifetime of brand X bulbs is known to be 4,500 hours with standard deviation of 450 hours. Part A A light bulb is selected at random find the probability that it will last...
3. ### Committee Combination

Hi. I have used the below formulation of the problem. Kindly let me know whether I am correct or wrong. Q. "A condominium management committee has 11 members and wishes to divide into three committees with everyone serving on at least one committee, and no one serving on more than one...
4. ### Finding Minimum Probability

Hi. Below is the question in my homework. I don't know whether I've to solve this using Bayes' theorem or I have to provide a general answer. "A mine pit has collapsed and 20 miners are stuck in an elevator under the mine pit. Since they are in the same elevator, assume we know that they...
5. ### Homework question: Conditional expectation on random variable itself

Hi: I am confused by the following problem. (Please also find attachment) Given X is a random variable, g is a real function of X mapped from R to R. (g:X=>R:R) (a) Find E[g(X)/X] (Find the expectation of E[g(X)/X] given X (b) Find Var(g(X)/X] Usually, we are only asked to find...
6. ### Probability and coincidences help

Can someone please help in the breakdown of how I do this question I am completely lost and I am not sure how to even word the answers 3. Suppose studies have shown that approximately 20% (.2) of Americans regularly engage in exercise (at least 3 times per week). a. If one American is...
7. ### Z-values and probability

Suppose concentration of arsenic (in ppb) in groundwater sampled quarterly from a particular well can be modeled with a normal distribution with a mean of 5 and a standard deviation of 1. a) What is the probability that a single observation will be given greater than 7ppb? z =5-7 / 1 = 2 And...
8. ### Risk probability assesment

Your exam could be marked with a range of possible grades, simplified as on the following state diagram: Acceptable To begin with the chances are that you will pass with a standard result. Each 45 minutes (the time allocated for each answer) your grade could go up or down to a...
I can not figure out what I believe might be an easy probability question: 1. What is the probability that if you buy a Fast 5 ticket, you will win $100 or more? 2. What is the probability that if you buy a Joker’s Wild ticket, you will win$100 or more? I have already determined the...