1) The mean lifetime of a tire is 36 months with a variance of49. If 126 tires are sampled, what is the probability that the meanof the sample would differ from the population mean by greater than0.44 months? Round your answer to four decimal places.
2) Suppose that a study of elementary school students reportsthat the mean age at which children begin reading is 5.5 years witha standard deviation of 1.1 years.
a) If a sampling distribution is created using samples of theages at which 47 children begin reading, what would be the mean ofthe sampling distribution of sample means? Round to two decimalplaces, if necessary.
b) If a sampling distribution is created using samples of theages at which 47 children begin reading, what would be the standarddeviation of the sampling distribution of sample means? Round totwo decimal places, if necessary.
3) A production manager at a wall clock company wants to testtheir new wall clocks. The designer claims they have a mean life of15 years with a variance of 25. If the claim is true, in a sampleof 41 wall clocks, what is the probability that the mean clock lifewould be less than 15.4 years? Round your answer to four decimalplaces.
