Practice 10 questions on STAT130 - Statistics at University of KwaZulu-Natal - Pinetown. Free AI-generated quiz on uNotes — track your score, retake anytime.
1In the physician golf study, with a sample size of 12 and the population standard deviation unknown, which distribution must be used to find the critical value for the hypothesis test concerning the mean?
2Based on the physician golf study data (n=12, x̄=22.8, s=15.4), calculate the test statistic used to test the claim that the population mean is less than 19.
3In the e-grocer scenario, Mrs. Smith wants to test if the average order exceeds R85 to ensure profitability. Which set of hypotheses is mathematically correct for this one-tailed test?
4For the e-grocer data (n=85, x̄=89.27, σ=18), calculate the Z-test statistic to determine if the mean order size is significantly greater than 85.
5If Mrs. Smith wants to estimate the mean order size within a margin of error of R5 at a 95% confidence level (Z=1.96) given σ=18, what is the minimum required sample size?
6In the hypothesis test for variance in the e-grocer study, if the calculated Chi-square test statistic is 77.59 and the critical value for a left-tailed test at 10% significance is 82.36, what is the correct statistical decision?
7Using the provided treadmill data (n=10, Σx=60, Σy=188, Σx²=446, Σxy=1006), calculate the slope (b) of the least squares regression line.
8Given the regression equation ŷ = 27.3 - 1.42x for the treadmill study, what is the predicted number of minutes an athlete can run if they consume 5 units of alcohol per week?
9In the shoe size regression model (ŷ = 130.45 + 4.75x), what does the value 4.75 represent in the context of the study?
10When constructing a 90% confidence interval for the variance of golf rounds (n=12), which values from the Chi-square table are required?
