This topic contains a solution. Click here to go to the answer

Author Question: The time it takes a mechanic to change the oil in a car is exponentially distributed with a mean of ... (Read 116 times)

Melani1276

  • Hero Member
  • *****
  • Posts: 516
The time it takes a mechanic to change the oil in a car is exponentially distributed with a mean of 5 minutes.
 a. What is the probability density function for the time it takes to change the oil?
  b. What is the probability that it will take a mechanic less than 6 minutes to change the oil?
  c. What is the probability that it will take a mechanic between 3 and 5 minutes to change the oil?

Question 2

A coal company wants to determine a 95 confidence interval estimate for the average daily tonnage of coal that it mines. Assuming the company reports that the standard deviation of daily output is 200 tons, how many days should it sample so that the margin of error will be 39.2 tons or less?



Related Topics

Need homework help now?

Ask unlimited questions for free

Ask a Question
Marked as best answer by a Subject Expert

Hikerman221

  • Sr. Member
  • ****
  • Posts: 346
Answer to Question 1

a. f(x) = (1/5) e-x/5 for x  0
b. .6988
c. .1809

Answer to Question 2

100




Melani1276

  • Member
  • Posts: 516
Reply 2 on: Jun 24, 2018
YES! Correct, THANKS for helping me on my review


lkanara2

  • Member
  • Posts: 329
Reply 3 on: Yesterday
Great answer, keep it coming :)

 

Did you know?

A headache when you wake up in the morning is indicative of sinusitis. Other symptoms of sinusitis can include fever, weakness, tiredness, a cough that may be more severe at night, and a runny nose or nasal congestion.

Did you know?

All adverse reactions are commonly charted in red ink in the patient's record and usually are noted on the front of the chart. Failure to follow correct documentation procedures may result in malpractice lawsuits.

Did you know?

During the twentieth century, a variant of the metric system was used in Russia and France in which the base unit of mass was the tonne. Instead of kilograms, this system used millitonnes (mt).

Did you know?

The average human gut is home to perhaps 500 to 1,000 different species of bacteria.

Did you know?

Vampire bats have a natural anticoagulant in their saliva that permits continuous bleeding after they painlessly open a wound with their incisors. This capillary blood does not cause any significant blood loss to their victims.

For a complete list of videos, visit our video library