Unit 3: Assignment
GB513-2: Apply hypothesis testing and probability analysis to solve business problems.
This assignment has two parts. Part 1 has questions about probability calculations. Part 2 has questions about hypothesis testing.
Part 1
Question 1
In a class where the exam averages are normally distributed, the mean score is 75 and the standard deviation is 15. If you want to find out the probability that a randomly picked student has scored 105 or above, what is the z-value that you should look up on the normal distribution table?
Question 2
According to a report by Scarborough Research, the average monthly household cellular phone bill is $73. Suppose local monthly household cell phone bills are normally distributed with a standard deviation of $22.
What is the probability that a randomly selected monthly cell phone bill is less than $95?
What is the probability that a randomly selected monthly cell phone bill is between $62 and $84?
Question 3
A Travel Weekly International Air Transport Association survey asked business travelers about the purpose for their most recent business trip. 19% responded that it was for an internal company visit. Suppose 950 business travelers are randomly selected.
What is the probability that more than 20% of the business travelers say that the reason for their most recent business trip was an internal company visit?
What is the probability that between 18% and 20% of the business travelers say that the reason for their most recent business trip was an internal company visit?
