$738.$ Th e manager for United SavVnge aSeskde Viginia, has worked with her cmplceeetort o reduce the waiting ine for cUstornershank She and the team conciuded that averae waiC is now down to $35$ minutes with a standartdeviatiot equal to $1$O minute. However bofoe maaateent at a anaers eeting. this brancmaage Wanted to double$-$check that the prccecWking as thogh. To make Ihis check, se raaple $25$ custoners and recorded the tie they hwat Sie dihcovered that iean wait tite torple et custeers ws $4,2$ minutes, Basod on elalS aot swaiting tim, what is theehity tha A sample mean foe n$25$ peebe as lae as oe Lareer than $4\mathrm{.}2$ miuesteeE conelude based om shese da