document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=1167362>Question 1167362</A>: <I><SPAN STYLE=\"word-break: break-all;\"> Assume that when adults with smartphones are randomly​ selected, 52​% use them in meetings or classes. If 11 adult smartphone users are randomly​ selected, find the probability that fewer than  5 <BR>\n" );
document.write( "of them use their smartphones in meetings or classes. </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #791960 by </B><A HREF=/tutors/aboutme.mpl?userid=Boreal><B>Boreal(15235)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=Boreal><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=Boreal><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=791960\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> this is a binomial with n=11 p=0.52 and want 0 to 4.<BR>\n" );
document.write( "Can do this by doing each calculation from 0 to 4 (e.g.,for p(4) it is 11C4*0.52^4*0.48^7) (=0.1416) p(0) 0.48^11=0.0003<BR>\n" );
document.write( "or <BR>\n" );
document.write( "binomcdf(11,0.52,4)=0.2312\r<BR>\n" );
document.write( "\n" );
document.write( "mean is 5.72 and variance is 2.76 (so sd 1.66), so approximately less than 1.22/1.66 sd and that gives a probability of 0.2327, so rough approximation a very reasonable check.<BR>\n" );
document.write( " </SPAN>\n" );
document.write( "</TD></TR></TABLE>\n" );