# Data Analysis

for sverma if available I have 4 questions please provide explanation if you can.

This assignment requires you to use Excel only in question 4. Questions 2, 3, and 4 require

that you explain how you determined the answer to the question. Submitting answers without

an explanation for these three questions is not sufficient.

submit your answers.

Question 1

A group of investors wants to develop a chain of fast-food restaurants. In determining potential costs

for each facility, they must consider, among other expenses, the average monthly electric bill. They

decide to sample some fast-food restaurants currently operating to estimate the monthly cost of

electricity. They want to be 90% conﬁdent of their results and want the error of the interval estimate to

be no more than $100. They estimate that such bills range from $600 to $2,500. How large a sample

should they take?

Question 2

Suppose a study reports that the average price for a gallon of self-serve regular unleaded gasoline is

$3.16. You believe that the ﬁgure is higher in your area of the country. You decide to test this claim

for your part of the United States by randomly calling gasoline stations. Your random survey of 25

stations produces the following prices (all in $). Assume gasoline prices for a region are normally

distributed. Do the data you obtained provide enough evidence to reject the claim? Use a 1% level of

signiﬁcance.

3.27 3.29 3.16 3.20 3.37

3.20 3.23 3.19 3.20 3.24

3.16 3.07 3.27 3.09 3.35

3.15 3.23 3.14 3.05 3.35

3.21 3.14 3.14 3.07 3.10

Question 3

Where do CFOs get their money news? According to Robert Half International, 47% get their money

news from newspapers, 15% get it from communication/colleagues, 12% get it from television, 11%

from the Internet, 9% from magazines, 5% from radio, and 1% do not know. Suppose a researcher

wants to test these results. She randomly samples 67 CFOs and ﬁnds that 40 of them get their

money news from newspapers. Does the test show enough evidence to reject the ﬁndings of Robert

Half International? Use a = .05. Unit 3 [GB513: Business Analytics]

Question 4

To answer this question, use the Data Analysis Toolpack in Excel and select “t-Test: Two-Sample

Assuming Equal Variances” from the list of available tools. Explain your answer (how did you decide if

men spend more) and include the output table. Some studies have shown that in the United States,

men spend more than women buying gifts and cards on Valentine’s Day. Suppose a researcher

wants to test this hypothesis by randomly sampling nine men and 10 women with comparable

demographic characteristics from various large cities across the United States to be in a study. Each

study participant is asked to keep a log beginning one month before Valentine’s Day and record all

purchases made for Valentine’s Day during that one-month period. The resulting data are shown

below. Use these data and a 1% level of signiﬁcance to test to determine if, on average, men actually

do spend signiﬁcantly more than women on Valentine’s Day. Assume that such spending is normally

distributed in the population and that the population variances are equal.

Men Women

107.48 125.98

143.61 45.53

90.19 56.35

125.53 80.62

70.79 46.37

83.00 44.34

129.63 75.21

154.22 68.48

93.80 85.84

126.11