Question 1

A candy bar manufacturer is interested in trying to estimate how sales are influenced by the price of their product. To do ,this the company randomly chooses 6 small cities and offers the candy bar at different prices. Using candy bar sales as the dependent variable, the company will conduct a simple linear regression on the data below:

City	Price ($)	Sales
River City	1.30	100
Hudson	1.60	90
Ellsworth	1.80	90
Prescott	2.00	40
Rock Elm	2.40	38
Stillwater	2.90	32

What is the coefficient of correlation for these data?Ans= -0.8854 (Show detailed workings)

Question 2

As an aid to the establishment of personnel requirements, the director of a hospital wishes to estimate the mean number of people who are admitted to the emergency room during a 24-hour period. The director randomly selects 64 different 24-hour periods and determines the number of admissions for each. For this sample, = 396 andS= 100. Find the confidence interval of admissions per 24-hour period with a 95% confidence interval.

Answer: 396 24.9793 or 371.0207 420.9793 (Show your workings or solution)

Question 3

A university dean is interested in determining the proportion of students who receive some sort of financial aid. Rather than examine the records for all students, the dean randomly selects 200 students and finds that 118 of them are receiving financial aid. Use a 90% confidence interval to estimate the true proportion of students who receive financial aid.

Answer: 0.59 0.057 or 0.533 0.647

Question 4

A manufacturer of power tools claims that the mean amount of time required to assemble their top-of-the line table saw is 80 minutes with a standard deviation of 40 minutes. Suppose a random sample of 64 purchasers of this table saw is taken. The probability that the sample mean will be greater than 88 minutes is ________.

Answer: 0.0548 (Show your solution)

Question 5

Suppose that history shows that 60% of college students prefer BrandCcola. A sample of 5 students is to be selected.

(a) Find the mean of this binomial distribution (Ans=3)

(b) Find the variance of the binomial distribution (Ans=1.2)

Show your workings