« 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 176 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?

During pregnancy, a woman is more likely to experience bleeding gums and nosebleeds caused by hormonal changes that increase blood flow to the mouth and nose.

Did you know?

Dogs have been used in studies to detect various cancers in human subjects. They have been trained to sniff breath samples from humans that were collected by having them breathe into special tubes. These people included 55 lung cancer patients, 31 breast cancer patients, and 83 cancer-free patients. The dogs detected 54 of the 55 lung cancer patients as having cancer, detected 28 of the 31 breast cancer patients, and gave only three false-positive results (detecting cancer in people who didn't have it).

Did you know?

Barbituric acid, the base material of barbiturates, was first synthesized in 1863 by Adolph von Bayer. His company later went on to synthesize aspirin for the first time, and Bayer aspirin is still a popular brand today.

Did you know?

The first successful kidney transplant was performed in 1954 and occurred in Boston. A kidney from an identical twin was transplanted into his dying brother's body and was not rejected because it did not appear foreign to his body.

Did you know?

The strongest synthetic topical retinoid drug available, tazarotene, is used to treat sun-damaged skin, acne, and psoriasis.

Range of Motion of the Wrist and Hand Joints, Radial and Ulnar Deviation of the Wrist Range of Motion of the Wrist and Hand Joints, Radial and Ulnar Deviation of the Wrist
simple squamous alveoli simple squamous alveoli
(A) Fibula and tibia communited fracture. (B) Simple, tranverse fracture. (C) Open fracture of the ... (A) Fibula and tibia communited fracture. (B) Simple, tranverse fracture. (C) Open fracture of the ...
(A) In hyperopia, light rays focus behind the retina, making it difficult to focus on objects at ... (A) In hyperopia, light rays focus behind the retina, making it difficult to focus on objects at ...
Apply passive touch over the eyes and cheeks to finish. Place the hands, using very light pressure, ... Apply passive touch over the eyes and cheeks to finish. Place the hands, using very light pressure, ...
Micrographs and drawings of three types of simple epithelia, with examples of their functions and lo Micrographs and drawings of three types of simple epithelia, with examples of their functions and lo
Video: Renal Failure

For a complete list of videos, visit our video library