the average age of its cus tomers is 40 or less A random sample of 60 customers

# The average age of its cus tomers is 40 or less a

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the average age of its cus-tomers is 40 or les's. A random sample of 60 customerswas surveyed" and the average customer age was found tobe 42.'7 yeflrs. Assunre the standard deviation for customerage is 8.0 ye&rs. Using a : 0.02, answer the followingquestions:a. Does this sample prornide enough evidence to refute theage claim made by Bob's Sporting Goods?p-valueWe reject Ho when the Pvalue isLWe Do not reject Ho when the pvalue is 7/ a. what excel function can we use to get the pvalue from our test statistic (z-score)t NORM , S " D I STWhen we have a two-tailed test, we multiply the pvalue by2-Together we will work this Problem:Y \$.\$ffi ?#ffiffi #3Re-solve the RubyTuesday problem described in YourTurn #2 uslng the gvalue approach to testLindsay's efforts to conclude that the average wait time for a table is less than 20 minutes usinga : 0.05,Hint: Because this is a one-tail (lower) test, the p-value is the area to the /eftof the test statistic, 2".Answer can be found on r. Page 'li|2Your turn:9.8 Boh's Sporting Goods believes the average age of its cus-tomers is 40 or less. A random sample of 60 customers: was sun eyecl- and the average customcr age was found tobe 4?3years. Assume the standnrd deviation for customerage is 8.0 years. Using a : 0'02' unswer the lbllowing'questions:a. Does this sample provide enough evidence to retute theage clainr rnade by Bob's Sporting Goods lb. Deterntine the p-value tbr thi's tesl.Let's do a 2-tailed test together:k" K,#ffi # 4Kellogg's has a process for filling boxes of Frosted Flakes cereal with 1B ounces of product when it isoperating properly. Too much product in the box is wasteful to Kellogg's, whereas too little product canlead to customer complaints. To determine if the filling process is performing as it should, a randomsample of 40 boxes was examined, and the average weight of a box was found to be 18'06 Ounces.Historically, the filling prgcess has a standard deviation of 0.25 ounces. Follow the six steps for conduct-ing a two-tail hypothesis test to determine if the filling process is operating properly, using a : 0,05'Answer can be found on P Page 432 step 1: f A<r.t fu, 't?." u.u"[t ^J- o-l-ttrno-{-'ox- l'14ott^"s"sStep 3: DU&rmi^t t0.t "fgrogor.to- eFt( cdl''Jt,^-*-n L, .l,Lc-{t SU.i- in the tailUStep 4:We can use the excel functiontailed test.We can use the excel functiontailed test.9.3 Hypothesis Testing for the Population Mean when o is UnknownOne-Tailed Test: Find t-score atTwo-Tailed Test: Find t-score with"gi\$t{S&in the tailT INV- to get the critical t-score for a one-'t lN V L1 to get the criticalt-score for a two-step5: .svwgar<- {0.- t-fu-st sfofistr-c- src ) u,itt^, ta- critrcJ+-sccrr{qStep 5:What excel function can be used to calculate the pvalue from the t-score test statistic?  #### You've reached the end of your free preview.

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• Fall '14
• Null hypothesis, Statistical hypothesis testing
• • •  