FIL E (U se Excel) A variety o f p a c k a g in g so lu tio n s ex ist for products th at m u st b e kept within a specific tem p eratu re range. Cold chain distribution is particularly useful in th e food and pharm aceutical industries. A packaging com pany is trying o u t a n e w p ack agin g material th at m igh t red uce t h e variation o f te m p e r a tu r e s in t h e box. It is b e lie v e d th a t th e tem p era tu re in th e b ox fo llo w s a normal distribution with both packaging materials. Inspectors random ly select 16 boxes of new and old packages, 24 hours after they are sealed for sh ip m en t, and report th e tem p eratu res in d egrees Celsius. We assum e that the tw o sam ples are drawn in d ep en d en tly from norm ally distributed populations. A p o r tio n o f t h e d a ta is s h o w n b e lo w ; t h e c o m p l e t e d ata, labeled P a c k a g in g , are available o n th e text w ebsite.

N e w P a c k a g e O ld P a c k a g e 3.98 5.79 4.99 6.42

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4.95 5.95

a. State th e appropriate h y p o th e se s to test w h eth er or not th e n e w packaging material reduces th e variation of tem p era tu res in th e box.

b. U se Excel's F.TEST fu n c tio n t o c a lc u la te t h e p -value.

c. Make a conclusion at th e 5% significance level. P-399