This topic contains a solution. Click here to go to the answer
« previous next »

Author Question: A light bulb manufacturer claims its light bulbs will last 500 hours on average. The lifetime of a ... (Read 1114 times)

haleyc112

  • Hero Member
  • *****
  • Posts: 600
on: Jun 24, 2018
A light bulb manufacturer claims its light bulbs will last 500 hours on average. The lifetime of a light bulb is assumed to follow an exponential distribution.
 a. What is the probability that the light bulb will have to be replaced within 500 hours?
  b. What is the probability that the light bulb will last more than 1,000 hours?
  c. What is the probability that the light bulb will last between 200 and 800 hours?

Question 2

A university planner wants to determine the proportion of spring semester students who will attend summer school. She surveys 32 current students and discovers that 12 will return for summer school.
 a. Construct a 90 confidence interval estimate for the proportion of current spring students who will return for summer school.
 b. With a .95 probability, what sample size would have to be selected to provide a margin of error of 3 or less?


Related Topics

Need homework help now?

Ask unlimited questions for free

Ask a Question
Marked as best answer by a Subject Expert

mariahkathleeen

  • Sr. Member
  • ****
  • Posts: 337
Reply #1 on: Jun 24, 2018
Answer to Question 1

a. .632
b. .135
c. .468

Answer to Question 2

a. .234 to .516
b. 1001


haleyc112

  • Hero Member
  • *****
  • Posts: 600
Reply #2 on: Jun 24, 2018
Correct answers!


mariahkathleeen

  • Sr. Member
  • ****
  • Posts: 337
Reply #3 on: Jun 24, 2018
Great! Please up vote :D


« previous next »
 

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.

Did you know?

Stevens-Johnson syndrome and Toxic Epidermal Necrolysis syndrome are life-threatening reactions that can result in death. Complications include permanent blindness, dry-eye syndrome, lung damage, photophobia, asthma, chronic obstructive pulmonary disease, permanent loss of nail beds, scarring of mucous membranes, arthritis, and chronic fatigue syndrome. Many patients' pores scar shut, causing them to retain heat.

Did you know?

A good example of polar molecules can be understood when trying to make a cake. If water and oil are required, they will not mix together. If you put them into a measuring cup, the oil will rise to the top while the water remains on the bottom.

Did you know?

Approximately one in three babies in the United States is now delivered by cesarean section. The number of cesarean sections in the United States has risen 46% since 1996.

Did you know?

People with high total cholesterol have about two times the risk for heart disease as people with ideal levels.

Two Scottish reindeer relax after pulling Santa's sleigh at the switching on of Christmas light Two Scottish reindeer relax after pulling Santa's sleigh at the switching on of Christmas light
Examples of Impacts Associated with Different Amounts of Global Average Temperat Examples of Impacts Associated with Different Amounts of Global Average Temperat
A typical 12 volt test light. A typical 12 volt test light.
Interactions of Light and Matter Interactions of Light and Matter
Massage the feet. Finish with light connecting strokes over the entire leg. Redrape the leg. Massage the feet. Finish with light connecting strokes over the entire leg. Redrape the leg.
Testing the corneal light reflex Testing the corneal light reflex
Video: Magnetic resonance imaging (MRI)

For a complete list of videos, visit our video library