The following histogram represent a sample of street vendors that was obtained from a street vendors' association meeting in the Johannesburg CBD in December of last year. December profits (R'000) Time left 0:53:38 Number of street vendors 52963 15 12 3 11 10 2 2-<5 5-8 8-<11 11-<14 14-<17 Profit (R'000) The 17 vendors who made the least profit earned less than...? O a. R5 000 O b. R8 000 O c. R11 000 O d. R14 000 O e. None of the above

A survey of 90 recently delivered women on the rolls of a county welfare department revealed that 27 had a history of intrapartum or postpartum infection. What is the critical value of z if we need to conclude that the population proportion with a history of intrapartum or postpartum infection is less than 0.25.

A tax accountant would like to test the claim that the proportion of individuals who owe when filing their taxes is less than 0.20. If the z− test statistic was calculated as z=−2.11, does the tax accountant have enough evidence to reject the null hypothesis? Assume α=0.005. Move the blue dot to choose the appropriate test (left-, right, or two-tailed). Then, use the graph below to show the test statistic, p-value, and the rejection region to make a conclusion about the hypothesis test. powered by Move the blue dot to choose the appropriate test α=0.01 α=0.025 α=0.05 α=0.1 Significance level = 0.01   Select the correct answer below: There is enough evidence to suggest the proportion of individuals who owe when filing their taxes is less than 0.20. There is not enough evidence to suggest the proportion of individuals who owe when filing their taxes is less than 0.20. There is enough evidence to suggest the proportion of individuals who owe when filing their taxes is greater than 0.20.…

Records for the last 15 years have shown that the average rainfall in a certain region of the country, for the month of March, to be 1.20 inches, with s = 0.45 inches. A second region had an average rainfall of 1.35 inches, with s = 0.54. estimate the difference of the true average rainfalls in those two regions as a 95% C.I. with the assumption of normal populations and unequal variances.

The time at which a bus arrives at a station is uniform over an interval (a,b) with mean 2:00 pm and variance 12 minutes. Determine the values of a and b.

A psychologist is studying the effects of lack of sleep on the performance of various perceptual-motor tasks. After a given period of sleep deprivation, a measurement of reaction time to an auditory stimulus was taken for each of 36 adult male subjects. The reaction times (in seconds) are summarized as follows:                 x = 1.82, s = 0.22   Previous psychological studies show that the true mean reaction time for non-sleep-deprived male subjects is 1.70 seconds.  Does the sample evidence indicate that the mean reaction time for sleep-deprived male subjects is  longer than that of non-sleep-deprived male subjects  ? α = 0.05 (i) The alternative hypothesis for the above problem is

A psychologist is studying the effects of lack of sleep on the performance of various perceptual-motor tasks. After a given period of sleep deprivation, a measurement of reaction time to an auditory stimulus was taken for each of 36 adult male subjects. The reaction times (in seconds) are summarized as follows:                 x = 1.82, s = 0.22  Previous psychological studies show that the true mean reaction time for non-sleep-deprived male subjects is 1.70 seconds. Does the sample evidence indicate that the mean reaction time for sleep-deprived male subjects is  longer than that of non-sleep-deprived male subjects  ? α = 0.05 (iii) The p-value for the above problem is

A psychologist is studying the effects of lack of sleep on the performance of various perceptual-motor tasks. After a given period of sleep deprivation, a measurement of reaction time to an auditory stimulus was taken for each of 36 adult male subjects. The reaction times (in seconds) are summarized as follows:                 x = 1.82, s = 0.22  Previous psychological studies show that the true mean reaction time for non-sleep-deprived male subjects is 1.70 seconds.  Does the sample evidence indicate that the mean reaction time for sleep-deprived male subjects is  longer than that of non-sleep-deprived male subjects  ? α = 0.05 (ii) The test statistic for the above problem is

Assume that anxiety scores as measured by an anxiety assessment inventory arenormally distributed with μ = 20 and σ = 4. A sample of 4 patients who areundergoing treatment for anxiety is randomly selected, and their mean anxiety scoreX = 22. Is the average anxiety score from patients who are under treatmentsignificantly different from 20? Assume a = .10.