Author Question: A rechargeable flashlight is advertised to last up to 2 1/2 hours per charge and to recharge ... (Read 33 times)

Frost2351

  • Hero Member
  • *****
  • Posts: 557
A rechargeable flashlight is advertised to last up to 2 1/2 hours per charge and to recharge overnight. A test was conducted which measured the time a light lasted before needing a recharge. A random sample of 12 lights has a mean recharge time of 2.24 hours and a standard deviation of 1.05 hours. Assuming the population for recharge time is normally distributed, what is the 99 confidence interval estimate for the population mean? ___________________ _ to ___________________ _
 Fill in the blank(s) with correct word

Question 2

An economics professor is taping 60-minute lectures for replay over the university radio station. To make sure that the brand of tapes that will be used records for at least sixty minutes, one dozen are purchased and examined to determine if they do record for sixty minutes. The results of the recording test in minutes show a mean of 61.28 and standard deviation of 3.868 . The professor assumes that the playing time is normally distributed. Construct an 80-percent confidence interval for the mean recording time employing these data. ___________________ _ to ___________________ _
 Fill in the blank(s) with correct word



IRincones

  • Sr. Member
  • ****
  • Posts: 321
Answer to Question 1

1.30; 3.18

Answer to Question 2

59.758; 62.802



Related Topics

Need homework help now?

Ask unlimited questions for free

Ask a Question
 

Did you know?

As of mid-2016, 18.2 million people were receiving advanced retroviral therapy (ART) worldwide. This represents between 43–50% of the 34–39.8 million people living with HIV.

Did you know?

The Centers for Disease Control and Prevention (CDC) was originally known as the Communicable Disease Center, which was formed to fight malaria. It was originally headquartered in Atlanta, Georgia, since the Southern states faced the worst threat from malaria.

Did you know?

The horizontal fraction bar was introduced by the Arabs.

Did you know?

Disorders that may affect pharmacodynamics include genetic mutations, malnutrition, thyrotoxicosis, myasthenia gravis, Parkinson's disease, and certain forms of insulin-resistant diabetes mellitus.

Did you know?

Addicts to opiates often avoid treatment because they are afraid of withdrawal. Though unpleasant, with proper management, withdrawal is rarely fatal and passes relatively quickly.

For a complete list of videos, visit our video library