Mathematics, 07.06.2021 06:50 fernandoramirez086
The lifetime of a certain brand of battery is known to have a standard deviation of 19 8 hours. Suppose that a random sample of 90 such batteries has a mean lifetime of 46 2 hours Sased on this sample, find a 90° confidence interval for the true mean lifetime of all batteries of this brand.
Answers: 2
Mathematics, 22.06.2019 03:00, ninigilford
Ben frank is an electrician who installs lighting fixtures. he charges (in dollars) his clients 15h+40f15h+40f where hh is the number of hours worked and ff is the number of fixtures installed. how much does ben frank charge when he works 77 hours and installs 99 fixtures?
Answers: 1
The lifetime of a certain brand of battery is known to have a standard deviation of 19 8 hours. Supp...