Reference no: EM133144364

BSB123 Data Analysis - Queensland University of Technology

Question One
Scores on a government psychometric test are normally distributed with a mean of 150 and a standard deviation of 25.
a. What is the probability an applicant scores more than 120 on the test?
b. What score would the top 20% of applicants achieve?

Question Two
Eight percent of the worlds population have blue eyes.
a. What is the probability that in a sample of 200 students more than 10% have blue eyes?
b. Answer the same question if the sample was only 100 students.

Question Three
In your excel spreadsheet there is a worksheet on Instagram v Facebook usage for different age groups.
a. Conduct a test at the 5% level of significance if Instagram usage among Under 50'S is more than 60%.
b. Conduct a test at the 1% level of significance if the proportion of Under 50's who use Instagram is more than the proportion of 50 and overs.

Question Four
In your excel spreadsheet there is a worksheet called on-line retailer.
a. An online retailer is looking at the changing trends in sales since pre-covid and 2022.
b. In pre-covid years the standard deviation in sales was $25. While overall spending online has increased, the retailer believes that the variance in sales has also increased. Test at the 5% level of significance if the variance of sales in 2022 is more than the previous $625.
Conduct a test to see if the average spend of customers in 2022 is more than that in 2019.

Attachment:- Data Analysis.rar