document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=1106314>Question 1106314</A>: <I><SPAN STYLE=\"word-break: break-all;\"> The process for manufacturing ball bearing results in weights that have an approximately normal distribution with mean of 0.15g and standard deviation 0.003g. <BR>\n" );
document.write( "A. If you select one ball bearing at random, what is the probability that it weights less than 0.148g?<BR>\n" );
document.write( "B. If you select four ball bearings at random, what is the probability that their mean weight is less than 0.148g?<BR>\n" );
document.write( "C. If you select ten ball bearings at random, what is the probability that their mean weight is less than 0.148g? </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #721275 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=721275\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> z=(x-mean)/sd or (xbar-mean)/sigma/sqrt(n)<BR>\n" );
document.write( "z=(0.148-0.150)/0.003=-2/3.  probability z< (-2/3) is 0.2525<BR>\n" );
document.write( "z=-0.002*sqrt(4)/0.003 or -4/3.  Probability z < -(4/3) is 0.0912<BR>\n" );
document.write( "z=-0.002*sqrt(10)/0.003=0.0174.  Notice the inverting of the denominator fraction so that sqrt(n) is in the numerator. </SPAN>\n" );
document.write( "</TD></TR></TABLE>\n" );