« previous next »

Author Question: The average lifetime of a light bulb is 3,000 hours with a standard deviation of 696 hours. A simple ... (Read 207 times)

azncindy619

  • Hero Member
  • *****
  • Posts: 562
on: Jun 24, 2018
The average lifetime of a light bulb is 3,000 hours with a standard deviation of 696 hours. A simple random sample of 36 bulbs is taken.
 a. What are the expected value, standard deviation, and shape of the sampling distribution of ?
  b. What is the random variable in this problem? Define it in words.
  c. What is the probability that the average life in the sample will be between 2,670.56 and 2,809.76 hours?
 d. What is the probability that the average life in the sample will be greater than 3,219.24 hours?
  e. What is the probability that the average life in the sample will be less than 3,180.96 hours?

Question 2

The mean of a standard normal probability distribution _____.
 a. is always equal to 1
  b. can be any value as long as it is positive
  c. can be any value
  d. None of the answers is correct.


ong527

  • Sr. Member
  • ****
  • Posts: 285
Reply #1 on: Jun 24, 2018
Answer to Question 1

a. 3,000; 116; normal
b. x, the average life in a sample of 36 bulbs
c. .0482
d. .0294
e. .9406

Answer to Question 2

d


Related Topics

Need homework help now?

Ask unlimited questions for free

Ask a Question
« previous next »
 

Did you know?

On average, someone in the United States has a stroke about every 40 seconds. This is about 795,000 people per year.

Did you know?

Asthma occurs in one in 11 children and in one in 12 adults. African Americans and Latinos have a higher risk for developing asthma than other groups.

Did you know?

In 2010, opiate painkllers, such as morphine, OxyContin®, and Vicodin®, were tied to almost 60% of drug overdose deaths.

Did you know?

About 3% of all pregnant women will give birth to twins, which is an increase in rate of nearly 60% since the early 1980s.

Did you know?

Ether was used widely for surgeries but became less popular because of its flammability and its tendency to cause vomiting. In England, it was quickly replaced by chloroform, but this agent caused many deaths and lost popularity.

A Simple Model of the Learning Process A Simple Model of the Learning Process
In 1891 William Dean Howells championed the poetry of Emily Dickinson: “This poetry is as characteri In 1891 William Dean Howells championed the poetry of Emily Dickinson: “This poetry is as characteri
Sample Diet for a College-Aged Female Weighing 132 Pounds, Assuming Light to Moderate Daily ... Sample Diet for a College-Aged Female Weighing 132 Pounds, Assuming Light to Moderate Daily ...
Examples of visual fields of simple cortical cells. Examples of visual fields of simple cortical cells.
Share of Hours Worked by Education Level, 1940–2008 Share of Hours Worked by Education Level, 1940–2008
Average quarterly presidential approval rating, from Eisenhower to Trump Average quarterly presidential approval rating, from Eisenhower to Trump
Video: Coronary Heart Disease

For a complete list of videos, visit our video library