document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=726754>Question 726754</A>: <I><SPAN STYLE=\"word-break: break-all;\"> 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 300 batteries.  Of these batteries, 225 last 30 hours or more.\r<BR>\n" );
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document.write( "Find the sample proportion.  The sample proportion is _______. (Use 2 decimal place such as X.XX)<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 #444788 by </B><A HREF=/tutors/aboutme.mpl?userid=jim_thompson5910><B>jim_thompson5910(35256)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=jim_thompson5910><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=444788\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> The sample size is 300. The number of successes are 225, so the sample proportion is \r<BR>\n" );
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document.write( "phat = x/n = 225/300 = 0.75\r<BR>\n" );
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document.write( "So the sample proportion is phat = <font color=\"red\">0.75</font>\r<BR>\n" );
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document.write( "Notes:\r<BR>\n" );
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document.write( "1) phat (pronounced pee-hat) is the sample proportion that estimates the population proportion p. This is NOT the same as the p-value. The symbol you'll most likely see for phat is <IMG STYLE=\"max-width:80%;\" src=\"http://latex.codecogs.com/gif.latex?\LARGE \hat{p}\" title=\"\LARGE \hat{p}\" /> (basically a p with a ^ directly over it)\r<BR>\n" );
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document.write( "2) x = number of successes and n = sample size\r<BR>\n" );
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document.write( "3) A \"success\" in this case is finding a battery that lasts 30 hours or more. If you find a battery that lasts less than 30 hours, then it's not a success and it's a failure.\r<BR>\n" );
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document.write( "4) The sample proportion (phat) is equal to the ratio or fraction of the number of successes (x) over the number in the sample (n) </SPAN>\n" );
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