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Web business You want to compare the daily sales for two different designs of Web pages for your Internet business. You assign the next 60days to either Design A or Design B, 30days to each.

(a) Describe how you would assign the days for Design A and Design B using the partial line of random digits provided below. Then use your plan to select the first three days for using Design A. Show your method clearly on your paper.

24005521142622439078

(b) Would you use a one-sided or a two-sided significance test for this problem? Explain your choice. Then set up appropriate hypotheses.

(c) If you plan to use Table B to calculate the P-value, what are the degrees of freedom?

(d) The t statistic for comparing the mean sales is 2.06Using Table B, what P-value would you report? What would you conclude?

Short Answer

Expert verified

(a) 21,24&55were selected for design A

(b)H0:μ1=μ2

Ha:μ1≠μ2

(c) The degree of freedom is 2929

(d) The P value is0.05

Step by step solution

01

Part (a) Step 1: Given Information

Given in the question that every day of the 60days a different number between1and60. we have to describe how you would assign the days for Design A and Design B using the partial line of random digits provided below. Then use plan to select the first three days for using Design A.

02

Part (a) Step 2: Explanation

choose the first two-digit number in the 1sttext

If the number falls between 1and60, choose the day for design A, then disregard the number and move on to the next 2-digit number. Repeat the process until design A has selected 30days, with repeated numbers being ignored. The remaining 30days will be used to construct A.

for the design A, locate the 1st3days

24⇒selectday24

00⇒ignore

55⇒selectday55

21⇒selectday21

therefore,21,24&55 were selected for design A

03

Part (b) Step 1: Given Information

We have to determine that a one-sided or a two-sided significance test for this problem and Then set up appropriate hypothesis.

04

Part (b) Step 2: Explanation

If a difference exists, testing is required, and a two-sided significance test is recommended. The null hypothesis states that the population's mean is the same:

H0:μ1=μ2

The alternative hypothesis states the opposite of the null hypothesis and utilizes the symbol since the two-sided significance test is used.

Hα:μ1≠μ2

05

Part (c) Step 1: Given Information

Given in the question that

n1=30

n2=30

we have to determine the degree of freedom.

06

Part (c) Step 2: Explanation

df=minn1-1,n2-1=min(30-1,30-1)=29

07

Part (d) Step 1: Given Information

Given in the question that

n1=30

n2=30

t=2.06

H0:μ1=μ2

Ha:μ1≠μ2

we have to find out the P value.

08

Part (d) Step 2: Explanation

The degree of freedom is 29

The P value is

0.04=2×0.02<P<2×0.025=0.05

P<0.05⇒rejectH0

There is sufficient evidence to support the notion that there is a difference.

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