document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=1201518>Question 1201518</A>: <I><SPAN STYLE=\"word-break: break-all;\"> 7. Cost of Dog Ownership. Money reports that the average annual cost of the first year of owning and caring for a large dog in 2017 is $1448. The Irish Red and White Setter Association of America has requested a study to estimate the annual first-year cost for owners of this breed. A sample of 50 will be used. Based on past studies, the popula- tion standard deviation is assumed known with σ = $255.\r<BR>\n" );
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document.write( "a. What is the margin of error for a 95% confidence interval of the mean cost of\r<BR>\n" );
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document.write( "the first year of owning and caring for this breed?\r<BR>\n" );
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document.write( "b. The file Setters contains data collected from fifty owners of Irish Setters on the\r<BR>\n" );
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document.write( "cost of the first year of owning and caring for their dogs. Use this data set to\r<BR>\n" );
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document.write( "compute the sample mean. Using this sumple, what is the 95% confidence inter-\r<BR>\n" );
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document.write( "val for the </SPAN>\n" );
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document.write( "Part (a)\r<BR>\n" );
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document.write( "n = 50 = sample size<BR>\n" );
document.write( "sigma = 255 = population mean\r<BR>\n" );
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document.write( "At 95% confidence, the z critical value is roughly z = 1.960 <BR>\n" );
document.write( "Use a table like this<BR>\n" );
document.write( "<a  rel=nofollow HREF= \"https://www.sjsu.edu/faculty/gerstman/StatPrimer/t-table.pdf\">https://www.sjsu.edu/faculty/gerstman/StatPrimer/t-table.pdf</a><BR>\n" );
document.write( "to get that value. Look at the bottom row labeled \"Z\" and above the 95% confidence level.<BR>\n" );
document.write( "A stats calculator can also compute this value.\r<BR>\n" );
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document.write( "Compute the margin of error for the mean.<BR>\n" );
document.write( "E = z*sigma/sqrt(n)<BR>\n" );
document.write( "E = 1.960*255/sqrt(50)<BR>\n" );
document.write( "E = 70.6823938474072<BR>\n" );
document.write( "E = 70.682394<BR>\n" );
document.write( "This value is approximate.<BR>\n" );
document.write( "Round this value however your teacher instructs.\r<BR>\n" );
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document.write( "Part (b)\r<BR>\n" );
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document.write( "You mentioned a file of the data values, but you didn't post the actual data.<BR>\n" );
document.write( "So I'm unable to do this part.\r<BR>\n" );
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document.write( "To compute the sample mean, add up the values and then divide by the number of values. Spreadsheet software is recommended. <BR>\n" );
document.write( "The spreadsheet function named AVERAGE will do both of these steps at once to get the sample mean right away.<BR>\n" );
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