document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=201545>Question 201545</A>: <I><SPAN STYLE=\"word-break: break-all;\"> On any given night, Becky has a 60% chance of seeing a shooting star in any given hour. If Becky watches the sky for two hours, find the following probabilities <BR>\n" );
document.write( "a.	What is the probability that Becky sees a shooting star in both hours?<BR>\n" );
document.write( "b.	What is the probability that Becky sees a shooting star in exactly one hour?<BR>\n" );
document.write( "c.	What is the probability that Becky does not see a shooting star at all?<BR>\n" );
document.write( "d.	Given that Becky did not see a shooting star in the first hour, what is the probability that she will see one in the second hour?\r<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 #151775 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=151775\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> On any given night, Becky has a 60% chance of seeing a shooting star in any given hour. If Becky watches the sky for two hours, find the following probabilities<BR>\n" );
document.write( "These are Binomial problems.<BR>\n" );
document.write( "p = 0.6 ; q = 0.4\r<BR>\n" );
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document.write( "a. What is the probability that Becky sees a shooting star in both hours?<BR>\n" );
document.write( "n = 2 ; = 0.6 ; x = 2<BR>\n" );
document.write( "P(x=2) = 0.6^2 = 0.36<BR>\n" );
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document.write( "b. What is the probability that Becky sees a shooting star in exactly one hour?<BR>\n" );
document.write( "P(x = 1) = 1 - [P(x=0) + P(x=2)] = 1 - (0.4)^2 - 0.6)^2 = 1 -0.16 - 0.36 = 0.48<BR>\n" );
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document.write( "c. What is the probability that Becky does not see a shooting star at all?<BR>\n" );
document.write( "P(x=0) = 0.4^2 = 0.16<BR>\n" );
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document.write( "d. Given that Becky did not see a shooting star in the first hour, what is the probability that she will see one in the second hour? <BR>\n" );
document.write( "The events are independent:<BR>\n" );
document.write( "P(x = 1 in the 2nd hour) = 0.6<BR>\n" );
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document.write( "Cheers,<BR>\n" );
document.write( "Stan H. </SPAN>\n" );
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