document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=230428>Question 230428</A>: <I><SPAN STYLE=\"word-break: break-all;\"> In testing a new drug, researchers found that 20% of all patients using it will have a mild side effect.  A random sample of 15 patients using the drug is selected.  Find the probability that:<BR>\n" );
document.write( "(a) exactly four will have this mild side effect.<BR>\n" );
document.write( "(b) at least seven will have this mild side effect.\r<BR>\n" );
document.write( "\n" );
document.write( "I understand how to do a, and I go the answer of .188, but I don't know how to do the setup for b.  I used the formula to calculate binomial probabilities for a, what do I do for be.  I'm not looking for an answer, I would just like the setup explained on how to get the answer.  Thanks 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 #170659 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=170659\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> In testing a new drug, researchers found that 20% of all patients using it will have a mild side effect. A random sample of 15 patients using the drug is selected. Find the probability that:<BR>\n" );
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document.write( "Binomial with n=15, p=0.2<BR>\n" );
document.write( "(a) exactly four will have this mild side effect.<BR>\n" );
document.write( "P(x=4) = 15C4(0.2)^4(0.8)^11) = 0.1876...<BR>\n" );
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document.write( "(b) at least seven will have this mild side effect.\r<BR>\n" );
document.write( "\n" );
document.write( "I understand how to do a, and I got the answer of .188, but I don't know how to do the setup for b.<BR>\n" );
document.write( "---<BR>\n" );
document.write( "You could add up P(x=7)+P(x=8)+....+P(x=15)<BR>\n" );
document.write( "OR<BR>\n" );
document.write( "You should have a binomial table in your text (or find one online)<BR>\n" );
document.write( "that will give you the p(0<= x <=6).  Subtract that number from 1<BR>\n" );
document.write( "and you will have P(7 <= x <= 15)<BR>\n" );
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document.write( "I get 0.0186..<BR>\n" );
document.write( "Cheers,<BR>\n" );
document.write( "Stan H. </SPAN>\n" );
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