document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=88341>Question 88341</A>: <I><SPAN STYLE=\"word-break: break-all;\"> I need help understanding how solve these types of problems...can someone explain them to me thanks...\r<BR>\n" );
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document.write( "1) two 6 sided dice are rolled. What is the probability that the sum of the two numbers on the dice will be greater than 9?\r<BR>\n" );
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document.write( "2) what i sthe probability that at least 2students in a class of 36 have the same birthday?\r<BR>\n" );
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document.write( "3) Consider determining how many possible phone numbers are in an area code (repeated numbers allowed). Is this a combination, a permutation, or neither? Provide an appropriate response. </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #64256 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=64256\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> 1) two 6 sided dice are rolled. What is the probability that the sum of the two numbers on the dice will be greater than 9?<BR>\n" );
document.write( "You should sketch the sample space (results of the experiment) as a 6x6 square<BR>\n" );
document.write( "with 1,2,3,4,5 6 on the left side and again on the top.<BR>\n" );
document.write( "Fill in the 36 entries on the square as the sum of the row and column the<BR>\n" );
document.write( "square is in.  You will get 36 entries that range from 2 to 36<BR>\n" );
document.write( "Count the number of entries that are greater than 9; then divide by 36<BR>\n" );
document.write( "That is the probability you are looking for.<BR>\n" );
document.write( "Answer = 6/36 = 1/6<BR>\n" );
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document.write( "2) what is the probability that at least 2 studentsin a class of 36 have the same birthday? <BR>\n" );
document.write( "The probability you and your mother share the same birthday is 1/365;<BR>\n" );
document.write( "Prob(2 or more of 36 have the same birthday) + P(no two have the same birthday )<BR>\n" );
document.write( "= 1<BR>\n" );
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document.write( "P(2 or more of 36 have the same birthday) = 1-P(no two have the same birthday)<BR>\n" );
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document.write( "Prob(no two have the same birthday) = (365/365)(364/365)(363/365)...(330/365)<BR>\n" );
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document.write( "Therefore Prob (2 or more have the same birthday) = 1-[(365!/329!)*1/365^36]\r<BR>\n" );
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document.write( "3) Consider determining how many possible phone numbers are in an area code (repeated numbers allowed). Is this a combination, a permutation, or neither? Provide an appropriate response.\r<BR>\n" );
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document.write( "I assume by \"in an area code\" means the number of 7-digit phone numbers <BR>\n" );
document.write( "possible associated with a particular area code.<BR>\n" );
document.write( "If that is so you have 10 ways to choose each of the 7 digit positions<BR>\n" );
document.write( "since repetition is allowed.  That is not a combination because you are <BR>\n" );
document.write( "not choosing groups that have no same elements; it is not a permutation<BR>\n" );
document.write( "because you are not choosing the various arrangement of 10 digits; it is<BR>\n" );
document.write( "an application of the general counting priciple which says \"if step one<BR>\n" );
document.write( "of a process can be performed in n ways and step two can be performed in<BR>\n" );
document.write( "m ways,then the two steps can be performed in n*m ways\". Your answer is<BR>\n" );
document.write( "10^7<BR>\n" );
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document.write( "Cheers,<BR>\n" );
document.write( "Stan H.<BR>\n" );
document.write( "Stan<BR>\n" );
document.write( "permutation<BR>\n" );
document.write( " </SPAN>\n" );
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