Suppose x has a distribution (not nessarily normal) with mean 50 and standard deviation 8. According to the Central Limit Theorem, which of the following is true?     For samples of size n = 16, is normal with mean 50 and standard deviation 1.     For samples of size n = 64, is normal with mean 50 and standard deviation 1.     For samples of size n = 16, is normal with mean 50 and standard deviation 8.     For samples of size n = 64,  is normal with mean 50 and standard deviation 8.

4. A distribution of scores has = 70.  The z-score for X = 65 is computed and a value of z = +1.00.  Regardless of the value of the standard deviation, why must this z-score be incorrect?

Suppose that the hemoglobin levels among healthy females are normally distributed with a mean of 14.1 gdL. Research shows that exactly 95% of healthy females have a hemogoblin level of 16.1 gdL. What is the standard deviation of the distribution of hemoglobin levels and healthy females. Carry you intermediate computations to atleast four decimal places, and round your answer to at least two decimal places.

Suppose x has a distribution with a mean of 65 and a standard deviation of 36. Random sample size n= 81 are drawn. Describe the x distribution and compute the mean and standard deviation of the distribution. Find the z value corresponding to x=77. Find p(x<77). Would it be unusual for a random sample of size 81 from the x distribution to have a sample mean less than 77

Suppose that scores on a particular test are normally distributed with a mean of 130 and a standard deviation of 15 . What is the minimum score needed to be in the top 2% of the scores on the test? Carry your intermediate computations to at least four decimal places, and round your answer to one decimal place.

Suppose that scores on a particular test are normally distributed with a mean of 120 and a standard deviation of 16. What is the minimum score needed to be in the top 10% of the scores on the test? Carry your intermediate computations to at least four decimal places, and round your answer to one decimal place.

Suppose that scores on a particular test are normally distributed with a mean of 120 and a standard deviation of 16. What is the minimum score needed to be in the top 15% of the scores on the test? Carry your intermediate computations to at least four decimal places, and round your answer to one decimal place.

Suppose that the speeds of car is traveling in California freeways are normally distributed with a mean of 63 mph. The highway patrols policy is to issue tickets for cars with speeds exceeding 80 mph. The records show that exactly 2% of the speed succeed this limit find the standard deviation of the speed of cars traveling on California’s freeway. Carry your intermediate computations to at least four decimal places in round your answer to at least one decimal place.

A population is known to be normally distributed with standard deviation known to be 8.5.  In order to test the hypothesis that the true value of the mean is 17 researchers collect a sample of size 33 and calculate the sample mean to be 14.  State the distribution of the sample mean and then test this hypothesis using the appropriate test.

Suppose that the average life of a refrigerator before replacement is μ = 15 years with a (68%of data) range from 13 to 17 years. Let x = age at which a refrigerator is replaced. Assumethat x has a distribution that is approximately normal. Find a good approximation for thestandard deviation of x values.