Problem 4

The following results were obtained from a multiple regression analysis of Mohideen supermarket profitability.The dependent variable, Y, is the profit (in Hundred of dollars) and the independent variables, X₁ and X₂, are the food sales and nonfood sales (in thousands of dollars).

CoefficientStandard Errort- valuep-value

Constant-15.062

X₁0.09720.0540.0750.132

X₂0.24840.0923.4570.0075

Coefficient of determination = 0.7139

a)Use the output shown above and write the equation that can be used to predict themonthly sales.

b)Interpret the coefficients of the estimated regression equation found in Part a.

c)What can you say about the strength of this relationship?

d)Carry out a test of whether X₁ and Y are significantly related.Use a .05 level of significance.

e)Carry out a test of whether X₂and Y is significantly related.Use a .05 level of significance.

Problem 5.) For a company below are monthly data on the transportation cost of its operations. This cost comes as a result of mining volumes, fuel charges and local road taxes in each month. These three variables more or less decide the total transportation cost the company incurs.

Coefficient

Std Err

t-value

p-value

Constant

-129.2135

105.4151

-1.2258

0.2380

Mining Volumes (in '000 tonnes)

-0.2474

0.1716

-1.4419

0.1686

Fuel Charges - in $ per tonne

9.1948

2.8312

3.2477

0.0050

Road Taxes - in $ per tonne

33.6106

3.9543

8.4997

0.0000

Coefficient of determination = 0.9139

f)Use the output shown above and write an equation that can be used to predict theTransportation cost.

g)Interpret the below two coefficients of the estimated regression equation found in Part a.

Mining Volumes:

Fuel Charges:

h)What can you say about the strength of this relationship?

i)Use a .05 level of significance, to explain which independent variable are significant and why.

Problem 6) SHORT ANSWER.Write the word or phrase that best completes each statement or answers the question.

1) The athletic departments at 10 randomly selected U.S. universities were asked by the Equal Employment Opportunity Commission to state what percentage of their nursing scholarships were presently held by women. The responses were 5, 4, 2, 1, 1, 2, 10, 5, 5, 5. Find the mean, median, mode, and geometric mean. Which is the most appropriate measure of central tendency? The least appropriate? Explain your answer. Is there an outlier?

1)_____________

2) The owner of a chicken farm kept track of each hen's eating and egg production for many months, with the results below. Which has more variation, feed consumption or egg output?

2)_____________

3) Bob's sample of freshman GPAs showed a mean of 2.72 with a standard deviation of 0.31. (a) What range would you predict for all the grades? For the middle 95 percent? Explain. (b) Why might your estimates be inaccurate?3)_____________

MULTIPLE CHOICE.Choose the one alternative that best completes the statement or answers the question.

4) Given the contingency table shown here, what is the probability that a mother smoked during pregnancy and had a college degree?

4) _______

A) .0803B) .0111C) .2385D) .0428

5) Given the contingency table shown here, what is the probability that a mother smoked during pregnancy or that she graduated from college?

5) _______

A) .3861B) .7850C) .0111D) .2591

6) Given the contingency table shown here, find the probability that a mother with some college smoked during pregnancy.

6) _______

A) .1117B) .1746C) .1078D) .1601

7) Given the contingency table shown here, what is the probability that a mother in the study smoked during pregnancy?

7) _______

A) .7401B) .5000C) .3174D) .2591