JAM007

HERE

1. The sampling distribution of the sample mean is a normal distribution for very small sample sizes regardless of the shape of the corresponding population distirubiton.

 True

 False

2 points   

Question 2

1. If the center of a sampling distribution is located at the parameter it is estimating, then we call that sampling distribution _________.

un biased

minimum variance

biased

random

2 points   

Question 3

1. In a manufacturing process a machine produces bolts that have an average length of 3 inches with a variance of .03. If we randomly select three bolts from this process, what is the probability the mean length of the bolt is at most 3.1 inches?

84.13%

100 %

71.57 %

28.43 %

15.87 %

2 points   

Question 4

1. Assume a binomial distribution with a sample size of 100 and the estimate of the population proportion equal to 0.10. Calculate the mean and standard deviation for the normal approximation to the binomial distribution for the random variable, x:

0.1, 0.0009

0.1, 0.030

10, 9

10, 3

Impossible to determine

2 points   

Question 5

1. A research and development laboratory researcher for a paint company is measuring the level of a certain chemical contained in a certain type of paint.  If the paint contains too much of this chemical, the quality of the paint will be compromised.  On the average, each can of paint contains 10% of the chemical.  How many cans of paint should be sampled if the researcher wants to be 98% certain of being within 1% of the true proportion of this chemical?

4887

1107

645

26