Samuel F.B. Morse (1791 – 1872), the creator of Morse Code, claimed that 12% of all letters used in the English language were “e”s.  Suppose random samples of 196 letters are selected from a book What is the standard deviation of the sampling distribution for the proportion of "e"s contained in the random sample of 196 letters?

In the EAI sampling problem, the population mean is $51,400 and the population standard deviation is $4,000. When the sample size isn = 20, there is a 0.4972 probability of obtaining a sample mean within ±$600 of the population mean. Use z-table. a. What is the probability that the sample mean is within $600 of the population mean if a sample of size 40 is used (to 4 decimals)? b. What is the probability that the sample mean is within $600 of the population mean if a sample of size 80 is used (to 4 decimals)?

A variable of a population has a mean of µ = 82 and a standard deviation of o = 9. a. Identify the sampling distribution of the sample mean for samples of size 81. b. In answering part (a), what assumptions did you make about the distribution of the variable? c. Can you answer part (a) if the sample size is 25 instead of 81? Why or why not? a. What is the shape of the sampling distribution? normal uniform skewed O bimodal What is the mean of the sampling distribution? Hi = (Simplify your answer.) What is the standard deviation of the sampling distribution? (Simplify your answer.) b. In answering part (a), what assumptions did you make about the distribution of the variable? A. It was assumed that the variable was normally distributed. B. No assumptions were made because, for a relatively large sample size, the sampling distribution is normal, regardless of the distribution of the variable under consideratio

Suppose samples of size 100 are drawn randomly from a population that has a mean of 20 and a standard deviation of 5. What is the probability of observing a sample mean equal to or greater than 20.5? 0.8384 0.4192 0.1634 0.9192 0.1587

If numerous samples of N = 15 are taken from a uniform distribution and a relative frequency distribution of the means is drawn, what would be the shape of the frequency distribution?

Suppose n=24 n=24 and p=0.4 What is the standard deviation of p?

What is the difference between s and o- ? O A. s is the standard deviation of a sample, and o- is the standard deviation of the population that the sample came from O B. s and o- are the same standard deviation O C.s is the standard deviation of all samples and o- is the standard deviation of a single sample O D.s is the standard deviation of a sample, and o- is the standard deviation of all sample means O E. s is the standard deviation of the population and 0 – is the standard deviation of all sample means

Question 2. A simple random sample of size n = 49 is obtained from a population with mean 80 and standard deviation 14. a. Describe the sampling distribution of x. b. What is P (x >83) c. What is P(x ≤ 75.8) d. What is P (78.3 < x < 85.1)