document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=750493>Question 750493</A>: <I><SPAN STYLE=\"word-break: break-all;\"> Psychologists estimate that 80% of male drivers, when lost in trying to find a location, continue to drive rather than asking for directions. If this estimate is correct, what is the probability that, in a random sample of 100 lost male drivers, the proportion who continue to drive is<BR>\n" );
document.write( "a) at least 0.70?<BR>\n" );
document.write( "b) less than 0.85?\r<BR>\n" );
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document.write( "please provide all step. I'm having a hard time understanding it. thank you </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #456634 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=456634\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> Psychologists estimate that 80% of male drivers, when lost in trying to find a location, continue to drive rather than asking for directions. If this estimate is correct, what is the probability that, in a random sample of 100 lost male drivers, the proportion who continue to drive is<BR>\n" );
document.write( "a) at least 0.70?<BR>\n" );
document.write( "z(0.7) = (0.7-0.8)/sqrt[0.8*0.2/199] = -2.5<BR>\n" );
document.write( "P(p-hat >= 0.7) = P(z >= -2.5) = normalcdf(-2.5,100) = 0.9938<BR>\n" );
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document.write( "b) less than 0.85? <BR>\n" );
document.write( "z(0.85) = (0.85-0.8)/sqrt(0.8*0.2/100) = 1.25<BR>\n" );
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document.write( "P(p-hat <= 0.85) = P(z <= 1.25) = 0.8944<BR>\n" );
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document.write( "Cheers,<BR>\n" );
document.write( "Stan H.<BR>\n" );
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