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Author Question: A population of 1,000 students spends an average of 10.50 a day on dinner. The standard deviation of ... (Read 82 times)

littleanan

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on: Jun 24, 2018
A population of 1,000 students spends an average of 10.50 a day on dinner. The standard deviation of the expenditure is 3 . A simple random sample of 64 students is taken.
 a. What are the expected value, standard deviation, and shape of the sampling distribution of the sample mean?
 b. What is the probability that these 64 students will spend a combined total of more than 715.21?
 c. What is the probability that these 64 students will spend a combined total between 703.59 and 728.45?

Question 2

If the mean of a normal distribution is negative, _____.
 a. the standard deviation must also be negative
  b. the variance must also be negative
  c. a mistake has been made in the computations, because the mean of a normal distribution cannot be negative
  d. None of the answers is correct.


diesoon

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Reply #1 on: Jun 24, 2018
Answer to Question 1

a. 10.5; .363; normal
b. .0314
c. .0794

Answer to Question 2

d


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