document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=366980>Question 366980</A>: <I><SPAN STYLE=\"word-break: break-all;\"> Hello Tutors, <BR>\n" );
document.write( "Glad you are here to help.\r<BR>\n" );
document.write( "\n" );
document.write( "a sample of 4 different calculators is randomly selected from a group containging 18 that are defective. and 35 with no defects. What is the probability that at least 1 calculator is defective. \r<BR>\n" );
document.write( "\n" );
document.write( "I started with adding all calculators together to get a total of 53. Then I divided 1/52 since we are looking for at least 1 defect out of 4.   the answer I got was .0189.  Is this correct?  \r<BR>\n" );
document.write( "\n" );
document.write( "If not, please solve and show your work. \r<BR>\n" );
document.write( "\n" );
document.write( "Thank you kindly  </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #261607 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=261607\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> A sample of 4 different calculators is randomly selected from a group containing 18 that are defective. and 35 with no defects. What is the probability that at least 1 calculator is defective.<BR>\n" );
document.write( "-----<BR>\n" );
document.write( "Binomial Problem with n = 4 and P(defective) = 18/(18+35) = 18/53<BR>\n" );
document.write( "And P(not defective) = 35/53<BR>\n" );
document.write( "--------------------------------------<BR>\n" );
document.write( "P(at least one defective) = 1 - P(none defective)<BR>\n" );
document.write( "P(at least one defective) = 1 - (35/53)^4 = 0.8098<BR>\n" );
document.write( "=============<BR>\n" );
document.write( "Cheers,<BR>\n" );
document.write( "Stan H. <BR>\n" );
document.write( " </SPAN>\n" );
document.write( "</TD></TR></TABLE>\n" );