I have this question which is stumping me and my lecture is little help.
For part we have to find the standard error and I have that, well I think I do, and part b and c depend on us getting part a right. Can someone please help me out.
The sign on the lift in a building states 'Maximum capacity 1120 kg or 16 persons'. A safety manager
wonders if the sign needs to be changed given that the weights of people who use the lift are normally
distributed with a mean of 68 kg and a standard deviation of 8 kg. The safety manager wants you to help
him with the following questions
(a). What is the standard error of the mean weight for a sample of 16 people?
So i have used the standard error formula and got 2 as the answer.
(b). How likely is the event that the maximum capacity of the lift will be exceeded when 16 persons enter the lift? Here I have use the central limit theorum and i get -26 as the answer, as you can see this is wrong.Can someone please help me figure this out?
(c). Should the sign on the lift be changed if acceptable risk of exceeding the maximum capacity, given that 16 persons enter the lift, is 20%?
Can anyone help me out here?
I have tried the Z=phat-p/p(1-p)/100 and I've used the binomial equation I just can't seem to get an answer that looks right.
PLEASE HELP ME OUT