document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=183099>Question 183099</A>This question is from textbook <A HREF=http://www.amazon.com/exec/obidos/ASIN/9780030923517/algebrahomeworkh>Study Guide: Review</A><BR>\n" );
document.write( ": <I><SPAN STYLE=\"word-break: break-all;\"> 13. The 10-number math team randomly selects 4 representatives to send to a meet. What is the probability that the 4 members chosen are the 4 with the lowest math grades?<BR>\n" );
document.write( "14. A 5-digit code is given to all cashiers at a store to let them log onto the cash register. What is the probability that an employee receives a code with all 5 numbers the same?\r<BR>\n" );
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document.write( "Explain why the events are independent and find the probability.<BR>\n" );
document.write( "25. rolling \"doubles\" 3 times in a row when rolling 2 number cubes<BR>\n" );
document.write( "26. selecting a red pen and then a blue pen, when selecting 2 pens from a bag of 10 red and 15 blue pens with replacement\r<BR>\n" );
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document.write( "Could you explain how to solve it?<BR>\n" );
document.write( "Thank you for your help. </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #137504 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=137504\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> 13. The 10-number math team randomly selects 4 representatives to send to a meet. What is the probability that the 4 members chosen are the 4 with the lowest math grades?<BR>\n" );
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document.write( "There are 10C4 = 210 sets of 4<BR>\n" );
document.write( "There is only one set that has the 4 lowest math grades<BR>\n" );
document.write( "P(4 lowest) = 1/210<BR>\n" );
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document.write( "14. A 5-digit code is given to all cashiers at a store to let them log onto the cash register. What is the probability that an employee receives a code with all 5 numbers the same? <BR>\n" );
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document.write( "Since repetition is allowed in the code there are 5^10 different codes.<BR>\n" );
document.write( "There are 10 codes that have all digits the same: 00000,11111,...,99999<BR>\n" );
document.write( "P(all digits are the same = 10/10^5 = 1/10^4 = 1/10,000<BR>\n" );
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document.write( "Explain why the events are independent and find the probability<BR>\n" );
document.write( "The events are independent because once you have selected a digit,<BR>\n" );
document.write( "that digit is replaced for the next selection. No selection depends<BR>\n" );
document.write( "on the previous selection.<BR>\n" );
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document.write( "25. rolling \"doubles\" 3 times in a row when rolling 2 number cubes<BR>\n" );
document.write( "P(doubles on one pair of dice) = 6/36 = 1/6<BR>\n" );
document.write( "P(doubles on three separage rolls) = (1/6)^3 = 1/216<BR>\n" );
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document.write( "26. selecting a red pen and then a blue pen, when selecting 2 pens from a bag of 10 red and 15 blue pens with replacement <BR>\n" );
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document.write( "Number of red/blue pairs = 10*15 = 150<BR>\n" );
document.write( "Number of unrestricted pairs: 25C2 = 300<BR>\n" );
document.write( "P(red/blue pair) = 150/300 = 1/2<BR>\n" );
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document.write( "Cheers,<BR>\n" );
document.write( "Stan H.<BR>\n" );
document.write( " </SPAN>\n" );
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