# binomial distribution

1. ### Is my approach correct for this binomial distribution question?

Here is the question:https://ibb.co/TLPVTmz So it would be: n = 5, p = 9/15 = 0.6 , q= 1-0.6 =0.4 P(x=3) = (5C3) * 0.6^3 *(0.4)^(5-3) = 0.3456 P(x=4) = (5C4) * 0.6^4 *(0.4)^(5-4) = 0.2592 P(x=5) = (5C5) * 0.6^5 *(0.4)^(5-5) = 0.07776 So adding the 3 prob = 0.68256 Ans. We will not...
2. ### Have I done this binomial distribution question correctly?

Insurance policies are sold to 10 different people age 25-30 years. All of these are in good health conditions. The probability that a person of similar condition will enjoy more than 25 years is 4/5. Calculate the probability that in 25 years a) Almost 2 will die. It will be P(X=0)...
3. ### [Excel] Determine errors that would have been encountered if required confidence for sample size was met (when it wasn't)

In my case, I perform an accuracy audits where, for example, my required accuracy is 99.90% and my required confidence level is 90.00%. In my case, the calculations are binomial; that is, a single test is either right or it's wrong, then I move to the next. There is no resampling. I use Excel...
4. ### Binomial Probability of Remaining Trials at a different X value

I am trying to find the binomial probability of the remaining trials in a binomial probability at a different probability of success on the leftover trials. My example: Number of Trials 6 Number of Successes 2 Prob of success on one trial: 75.8% Binomial probability output: 2.95% Out of my...
5. ### P charts based on binomial distribution - Statistical Process Control

Hello all, I have a question related to the use of p-chart in a process where there are defect rates measured. The control limits for this type of chart is calculated with +/- 3 sigmas around the mean (with mean = np and sd = sqrt(n*(1-p)*p)) As it is using i +/- 3 sigmas it assumes that we...
6. ### Normal Distribution?

I have a fairly large sample size of tenants and their average length of stay. When I try to put the data into a histogram, I don't seem to get a normally distributed data set because there is a large number of tenants that stay a short time period and then I have another large number of tenants...
7. ### Can I use a Poisson distribution for non-normal binomial data?

Hello all. I'm working on the following question: Fifteen percent of the items produced by a machine are defective. Out of 15 items chosen at random, a)what is the probability that exactly 3 items will be non-defective? Now this is a binomial distribution but; pn = 85/100 (15) = 12.75 and qn =...
8. ### Am I using the binom.dist properly?

Q -Stats classhas 60 students in it. The class lasts for three hours and the students ask questions at a rate of about 3 questions per hour. Model this situation with an appropriate binomial distribution and determine the probability of receiving more than 5 questions in a class. My answer...
9. ### programme evaluation: normal approximation to binomial

Housing first is an approach to reducing homelessness. Supposedly, it has 80 percent success rate, which means that on average 80 percent of programme participants tend to retain their housing, and not fall back to homelessness. It is also said that to reliably evaluate the effectiveness of...
10. ### Trying to write R function, binomial distribution

Hello! I am looking for some help with an Intro to R homework from a professor who doesn't clearly explain the things we need to know for the homework in class...:shakehead:confused: I'm trying to figure out how to write a function to simulate the sampling distribution of the mean when the...
11. ### Sudokua problem using related binomial distribution

It is given: If you succeed to solve a Sudoku with probability 0.4 and you try many times, how likely is it that you succeed twice before you fail 5 times? What is the expected number of failures before two successes? I don't understand which one between the binomial, geometric, negative...
12. ### Binomial Distribution : Probability equation solution

Question :In a binomial distribution for p=.48, q=1-p=.52 find the population size n1 so that P(X>=3)=.95 My solution : P(X>=3)=.95 can be rewrite as P(X=0)+P(X=1)+P(X=2)=.05 ------------------------------------------ eq(1) but i am un able to solve the above equation for n1, Is...
13. ### Minimum P to sample boxes

I have N boxes, each of which may or may not contain a ball. I want to know how many boxes have balls by sampling the boxes in the following way. For each box in the N boxes: I open this box with probability P If at the end I find out K boxes have a ball, I estimate the number of boxes...
14. ### Sampling distribution of the sample proportion.

A random sample of 20 students is selected. What is the probability that the sample proportion exceeds 75%, i.e., more than 15 students (out of 20 selected) will agree that that the course is interesting? You may leave your answer as, for example, 1 − 0.88. (As a standard error use 0.8. Also...
15. ### Comparing a Binomial and Normal Distribution

So I'm currently analyzing several sets of data, that all represent the exact same type of data. There are multiple sets of this data, but however are in different forms. That is, some of this data is in the binary form, either presence of absence, while others are in the quantitative form. My...
16. ### Is this variable following a poisson distribution or a binomial distribution?

You're at a bus stop watching people go by, not buses. Let X = number of people wearing headphones
17. ### Random Variable of two other random variables. Confusion to the max!

Here is the question at hand: I don't even know how to begin this question. I'm not looking for a complete solution per se but I don't even know where to begin. Suppose that X is a binomial random variable with parameters (m, θ) and Y is another binomial random variable with parameters (n...
18. ### Binomial Test in Excel

What is the probability of getting AT LEAST 79 out of 90 correct on a True or False test if you are guessing on every question? I think I need to do a cumulative binomial test for this. But I don't know how to do this in Excel. Would it be =Binomdist(79, 90, .5, FALSE) or would it be...
19. ### How to calculate variance of binomial variable where base (n) is binomial also

Hi I have a survey that collects data from each respondent on gender and also on attitudes. We don't know in advance how many men or women will be identified. We then ask attitudinal questions of each and wish to test for differences between the male and female groups. It seemed...
20. ### Power test - which one is suitable for me

I have a group of 200 female individuals that are either infected or uninfected. The infected proportion is known at generation (G) 0 when I mixed infected and uninfected females at 10% (therefore 20 infected, 180 uninfected). This infection frequency is expected to increase in each...