document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=878785>Question 878785</A>: <I><SPAN STYLE=\"word-break: break-all;\"> Telephone numbers in the US start with a 3 digit area code followed by a 7 digit local number.  Assume that any number (0-9) is possible for each digit.\r<BR>\n" );
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document.write( "a)	How many different area codes are possible?<BR>\n" );
document.write( "b)	What is the probability that an area code starts with a 5?<BR>\n" );
document.write( "c)	For a given area code, how many different local numbers are possible?<BR>\n" );
document.write( "d)	How many different complete telephone numbers are possible? <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 #530283 by </B><A HREF=/tutors/aboutme.mpl?userid=Alan3354><B>Alan3354(69443)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=Alan3354><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/cgi-bin/show-face.mpl?user=Alan3354><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=530283\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> Telephone numbers in the US start with a 3 digit area code followed by a 7 digit local number.  Assume that any number (0-9) is possible for each digit.\r<BR>\n" );
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document.write( "a)	How many different area codes are possible?<BR>\n" );
document.write( "3 decimal digits.  What do you think?<BR>\n" );
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document.write( "b)	What is the probability that an area code starts with a 5?<BR>\n" );
document.write( "5 is 1 of 10 possibilities.<BR>\n" );
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document.write( "c)	For a given area code, how many different local numbers are possible?<BR>\n" );
document.write( "7 decimal digits.<BR>\n" );
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document.write( "d)	How many different complete telephone numbers are possible?<BR>\n" );
document.write( "10 decimal digits --> <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=10%5E10 ALIGN=MIDDLE  ALT=\"10%5E10\"   DISABLED_style= \"max-width:90%; height:auto;\" >\r<BR>\n" );
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