Can you write out the questions exactly as they were presented to you.
I've been trying to figure out the answer to these two problems for weeks, but I can't seem to figure out how to do them. Please let me know if you can help.
1) A random variable X follows a normal distribution mean mu and standard dev 14. If P(X>148)=.96835 find mu
2) A researcher is studying unemployment among insurance executives. He wishes to estimate mu, the average length of unemployment for this specific population. He plans to take a random sample of 36 recently employed insurance executives, and to estimate mu using the mean or the sample. Find the probability that the sampling error for his estimate is less than 1.26 weeks.
Can you write out the questions exactly as they were presented to you.
Stop cowardice, ban guns!
That is the way the problems were presented. That's part of the reason I'm a bit lost.
The difference between stupidity and genius is that genius has its limits.
"Albert Einstein"
meaght12 (12-11-2014)
I understand what you are saying, but I'm still a bit lost. We are told to be able to do this problem with the Norm.Dist or Norm.Inv function in excel so I'm not sure how to do it by hand.
Last edited by askazy; 12-11-2014 at 04:29 PM.
The difference between stupidity and genius is that genius has its limits.
"Albert Einstein"
X = NORM.INV(probability, mean, standard deviation); for Standard Normal distribution mean = 0, s = 1.
Z = NORM.INV(1-0.96865, 0, 1) = -1.86131
Z = (X - mu)/s
-1.86131 = (148 - mu)/14, solve for mu.
See graph to visualize.
Tweet |