Question

1. Based on the CLT if the population sigma = 200 and the number of data samples collected is 4, the estimated standard deviation of the sample standard deviation will equal:

2. A sample of 200 widgets was sampled for defects and determined to be normally distributed. If the population standard deviation=2 and Xbar=7 you estimate the Upper Confidence interval at 95% confidence level to equal ? Given K=1.96

3. In Hypothesis testing a Type 1 error is defined as: a) alpha risk, b)beta risk, c) power, d) 1- beta, e) 1- alpha

4. If the sample data set distribution is symmetric, and n= 10 then the following statement is true: a) we can apply the CLT, b) we can apply the CLP, c) we can apply the USL, d) we can apply the LSL

5. When performing a 2-sample t- Test the statement: X1=X2 can be classified as: a) Ho, b) Hp, c) Ha, d) Hc

Answer 1

If x1,x2,...xn denote all the values from the population, then (population) standard deviation sigma is given by

Where is the mean of population.

If x1,x2,...xn denote all the values from the sample, then (sample) standard deviation s is given by

Where is sample mean;

Now we have popuation standard deviation given . we can calculate sample standard deviation from following formula.

so .

The population size is not given in question, insert it and you will get the answer.