Math- Statistics

posted by Tammy

A random sample of size 36 is to be selected from a population that has a mean μ = 50 and a standard deviation σ of 10.

* a. This sample of 36 has a mean value of , which belongs to a sampling distribution. Find the shape of this sampling distribution.
* b. Find the mean of this sampling distribution.
* c. Find the standard error of this sampling distribution.
* d. What is the probability that this sample mean will be between 45 and 55?
* e. What is the probability that the sample mean will have a value greater than 48?
* f. What is the probability that the sample mean will be within 3 units of the mean?

  1. PsyDAG

    a. Sample mean not given, expect normality.

    b. Without more info, expect sample mean = pop. mean

    c. SEm = SD/√(n-1), but you can just use n

    d, e, f. Z = (score-mean)/SEm

    Find table in the back of your statistics text labeled something like "areas under normal distribution" to find the proportions related to these Z scores.

Respond to this Question

First Name

Your Answer

Similar Questions

  1. statistics

    The scores of students on the ACT college entrance examination in a recent year had a normal distribution with a mean of 18.6 and a standard deviation of 5.9. A simple random sample of 50 students who took the exam is selected for …
  2. Statistics

    he Oil Price Information Center reports the mean price per gallon of regular gasoline is $ 3.79 with a population standard deviation of $ 0.18. Assume a random sample of 40 gasoline stations is selected and their mean cost for regular …
  3. Statistics

    1. The scores of students on the ACT college entrance examination in a recent year had a normal distribution with a mean of 18.6 and a standard deviation of 5.9. A simple random sample of 60 students who took the exam is selected for …
  4. Statistics

    A random sample of size 36 is to be selected from a population that has a mean μ = 50 and a standard deviation σ of 10. - - Find the mean of this sampling distribution. - Find the standard error of this sampling distribution.
  5. statistics

    random sample of n = 16 scores is selected from a normal distribution with a mean of μ = 50 and standard deviation of σ = 10. a. what is the probability that the sample mean will have a value between 45 and 55?
  6. Statistics

    The null and alternate hypotheses are: H0: μ1 = μ2 H1: μ1 ≠ μ2 A random sample of 15 items from the first population showed a mean of 50 and a standard deviation of 5. A sample of 12 items for the second population …
  7. statistics

    A specific study found that the average number of doctor visits per year for people over 55 is 8 with a standard deviation of 2. Assume that the variable is normally distributed. 1. Identify the population mean. The population mean …
  8. statistics

    Suppose a random sample of size 50 is selected from a population with σ = 10. Find the value of the standard error of the mean in each of the following cases (use the finite population correction factor if appropriate). a. The …
  9. statistics

    Suppose a random sample of size 50 is selected from a population with σ = 10. Find the value of the standard error of the mean in each of the following cases (use the finite population correction factor if appropriate). a. The …
  10. sda high

    A population has a mean of 200 and a standard deviation of 50. Suppose a simple random sample of size 100 is selected and is used to estimate μ. What is the probability that the sample mean will be within 5 of the population …

More Similar Questions