Question 1196343: A film-processing company claims that the owners of digital cameras store on average more than fifteen
pictures on their cameras, before the eventually download these to a computer or print. A random sample
of 10 digital camera owners produced the data below on the number of pictures stored on their digital
cameras.
25, 6, 22, 26, 31, 18, 13 20, 14, 2
3.1) Test this claim at the 10 % level of significance. (10 marks)
3.2) Estimate with 95 % confidence the mean number of pictures stored on digital cameras.
(5 marks)
Answer by Boreal(15235)   (Show Source):
You can put this solution on YOUR website! the mean is 17.7 pictures
s=9.08
the t value for (0.975, df=9) is 2.262
the half-interval is t*s/sqrt(10)=6.50
the CI is (11.2, 24.2) pictures are the unit
-
Ho: mean is <=15
Ha: mean is >15
alpha=0.10 p {reject Ho\Ho true}
test is a t (0.95, df=9) for a critical value of t= 1.833
t=(17.7-15)/s/qrt(n)
=1.6*sqrt(10)/9.08=0.94 Insufficient evidence to say that the mean is >15. The sample number is but the p-value of 0.19 says that if the sample mean were 15, there would be a 19% chance of having a value of this or more extreme.
|
|
|
