Suppose x has a distribution with a mean of 80 and a standard deviation of 45. Random samples of size n = 36 are drawn. Find P(x < 87.5)
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Suppose x has a distribution with a
Find P(x < 87.5)
Please show the steps to finding the answer and use a ti-83+ calculator since this is what I am working with.
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- An IQ test is designed so that the mean is 100 and the standard deviation is 24 for the population of normal adults. Find the sample size necessary to estimate the mean IQ score of statistics students such that it can be said with 95% confidence that the sample mean is within 8 IQ points of the true mean. Assume tha σ=24 and determine the required sample size using technology. Then determine if this is a reasonable sample size for a real world calculation.The required sample size is enter your response here. (Round up to the nearest integer.) Would it be reasonable to sample this number of students? Yes. This number of IQ test scores is a fairly small number. No. This number of IQ test scores is a fairly small number. Yes. This number of IQ test scores is a fairly large number. No.This number of IQ test scores is a fairly large number.Use the formula to find the standard error of the distribution of differences in sample means, x⎯⎯1−x⎯⎯2x¯1-x¯2.Samples of size 100 from Population 1 with mean 95 and standard deviation 10 and samples of size 80 from Population 2 with mean 76 and standard deviation 17Round your answer for the standard error to two decimal places.standard error =Use the formula to find the standard error of the distribution of differences in sample means, ₁ - X₂. Samples of size 105 from Population 1 with mean 86 and standard deviation 13 and samples of size 80 from Population 2 with mean 73 and standard deviation 16 Round your answer for the standard error to two decimal places. standard error =
- If the population average height is 67" and you take a random sample of 25 people resulting in a sample average value of 66 with a standard deviation of 2. Determine the "t" score that you would use as a test score for this data, and solve it for "t".Jeremiah earned a score of 530 on Exam A that had a mean of 450 and a standard deviation of 40. He is about to take Exam B that has a mean of 63 and a standard deviation of 20. How well must Jeremiah score on Exam B in order to do equivalently well as he did on Exam A? Assume that scores on each exam are normally distributed.Greg is in his first semester at a university and is taking a calculus course with a large enrollment. He just took the first midterm exam and is nervous about his score. Among all the students in the course, the mean of the exam was 85 with a standard deviation of 15.Find that grag has obtain less then 95.
- Use the formula to find the standard error of the distribution of differences in sample means, x¯1-x¯2.Samples of size 115 from Population 1 with mean 94 and standard deviation 14 and samples of size 85 from Population 2 with mean 75 and standard deviation 17Round your answer for the standard error to two decimal places.standard error = Enter your answer in accordance to the question statementThe Weather Underground reported that the mean amount of summer rainfall for the northeastern US is at least 11.52 inches. Ten cities in the northeast are randomly selected and the mean rainfall amount is calculated to be 7.42 inches with a standard deviation of 1.3 inches. At the α = 0.05 level, can it be concluded that the mean rainfall was below the reported average? What if α = 0.01? Assume the amount of summer rainfall follows a normal distribution. Please also state if the assumption of normal distribution was essential for solving this question. You will need to specify the appropriate hypothesis, identify the statistical test, estimate p-value (using R command), and state your conclusion in the context of the problem. For the conclusion, please use the following template. If you reject the null writeSince p-value is [write the value of your p-value] and is less than [write the value of alpha inpercent] we reject the null hypothesis at [write the value of alpha]% significance…Among 157 Cuban American men ,the mean systolic blood pressure was 146 mm Hg with a standard deviation of 27. We wish to know if based on these data, we may conclude that the mean systolic blood pressure for a population of Cuban American is greater than 140. Use α=0.01 (solve without excel) , show work
- On an exam, there is a mean score of 80 with a standard deviation of 12 If each exam is multiplied by 1.2, what will mean and standard deviation be? Please show computationA sample is selected from a population with = 150. After a treatment is administered to the individuals, the sample mean is found to be = 140 and the standard deviation is S= 9. If the sample has n = 18 scores, determine whether the sample is sufficient to conclude that the treatment has significant effect. Use a two tail test with = 0.02.
