document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=472941>Question 472941</A>: <I><SPAN STYLE=\"word-break: break-all;\"> 1.	A company that produces flashlight batteries wishes to know what percentage of its batteries will last longer than 30 hours. It selects and tests a random sample of 1,100 batteries. Of these batteries, 1,065 last 30 hours or more.\r<BR>\n" );
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document.write( "Find the 95% confidence interval for the percentage of batteries that last 30 hours or more. Please round the answers to the nearest tenth.\r<BR>\n" );
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document.write( "a. 	95.5% to 97.9%<BR>\n" );
document.write( "b. 	95.8% to 98.2%<BR>\n" );
document.write( "c. 	95.5% to 98.2%<BR>\n" );
document.write( "d. 	95.8% to 97.9%<BR>\n" );
document.write( "e. 	95.9% to 97.7%\r<BR>\n" );
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document.write( "2. Find the standard error for a sample proportion of 50%, given the following sample size. 50\r<BR>\n" );
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document.write( "a. s 0.070<BR>\n" );
document.write( "b. s 0.062<BR>\n" );
document.write( "c. s 0.071<BR>\n" );
document.write( "d. s 0.083<BR>\n" );
document.write( "e. s 0.056<BR>\n" );
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document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #324301 by </B><A HREF=/tutors/aboutme.mpl?userid=stanbon><B>stanbon(75887)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=stanbon><IMG SRC=http://www.algebra.com/images/aboutme-small.gif BORDER=0 alt=\"About Me\" VALIGN=MIDDLE></A>&nbsp;<IMG SRC=http://www.algebra.com/images/nopicture.jpg><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=324301\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> 1. A company that produces flashlight batteries wishes to know what percentage of its batteries will last longer than 30 hours. It selects and tests a random sample of 1,100 batteries. Of these batteries, 1,065 last 30 hours or more. <BR>\n" );
document.write( "Find the 95% confidence interval for the percentage of batteries that last 30 hours or more. Please round the answers to the nearest tenth.<BR>\n" );
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document.write( "sample proportion: 1065/1100 = 0.968<BR>\n" );
document.write( "ME = 1.96*sqrt[0.968*0.032/1100] = 0.010<BR>\n" );
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document.write( "95% CI: 0.968-0.010 < p < 0.968+0.010<BR>\n" );
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document.write( "95% CI: 0.958 < p < 0.978<BR>\n" );
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document.write( "a. 95.5% to 97.9%<BR>\n" );
document.write( "b. 95.8% to 98.2%<BR>\n" );
document.write( "c. 95.5% to 98.2%<BR>\n" );
document.write( "d. 95.8% to 97.9%<BR>\n" );
document.write( "e. 95.9% to 97.7% <BR>\n" );
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document.write( "2. Find the standard error for a sample proportion of 50%, given the following sample size. 50 <BR>\n" );
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document.write( "std of sample proportions: sqrt[0.5*0.5/50] = 0.0707..<BR>\n" );
document.write( "Cheers,<BR>\n" );
document.write( "Stan H.<BR>\n" );
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document.write( "a. s 0.070<BR>\n" );
document.write( "b. s 0.062<BR>\n" );
document.write( "c. s 0.071<BR>\n" );
document.write( "d. s 0.083<BR>\n" );
document.write( "e. s 0.056\r<BR>\n" );
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