document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=364121>Question 364121</A>: <I><SPAN STYLE=\"word-break: break-all;\"> I am having trouble with this homework problem:<BR>\n" );
document.write( "North Carolina State University posts the grade distributions for its courses online. 5 Students in Statistics 101 in the Fall 2007 semester received 26% A’s, 42% B’s, 20% C’s, 10% D’s, and 2% F’s. Choose a Statistics 101 student at random. To “choose at random” means to give every student the same chance to be chosen. The student’s grade on a four-point scale (with A = 4) is a discrete random variable X with this probability distribution:<BR>\n" );
document.write( "x=0 probability=0.02<BR>\n" );
document.write( "x=1 probability=0.10<BR>\n" );
document.write( "x=2 probability=0.20<BR>\n" );
document.write( "x=3 probability=0.42<BR>\n" );
document.write( "x=4 probability=0.26<BR>\n" );
document.write( "(a) Say in words what the meaning of P(X &#8805; 3) is. What is this probability?<BR>\n" );
document.write( "(b) Write the event “the student got a grade poorer than C” in terms of values of the random variable X. What is the probability of this event?\r<BR>\n" );
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document.write( "For (a) I said: if P(x>_3) then P is either less than or equal to 3 and this means that P is .42+.26 all added together to reach the probability of .68 or 68% chance the students grade is at least a B or better.<BR>\n" );
document.write( "For (b) I said that if the student got a grade poorer than C than P(x<2)or P(x<or equal to 1)= .10+.02 = .12 or 12%\r<BR>\n" );
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document.write( "Is this correct?\r<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 #259705 by </B><A HREF=/tutors/aboutme.mpl?userid=ewatrrr><B>ewatrrr(24785)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=ewatrrr><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=ewatrrr><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=259705\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> <PRE STYLE=\"white-space: pre-wrap; white-space: -moz-pre-wrap; white-space: -pre-wrap; white-space: -o-pre-wrap; word-wrap: break-word;\"><font size = 3 color = \"indigo\"><b><BR>\n" );
document.write( "Hi,<BR>\n" );
document.write( "x = 4 , 3 , 2 , 1, 0 represents an A,B,C,D or F grade<BR>\n" );
document.write( "P(X &#8805; 3)<BR>\n" );
document.write( "(a) Say in words what the meaning of P(X &#8805; 3) is.<BR>\n" );
document.write( "What is this probability of a student receiving a grade of B or better in Stat 101 <BR>\n" );
document.write( "P(X &#8805; 3)= P(3)+ P(4) = .42 + .26 = .68 Or 68%<BR>\n" );
document.write( "(b) Write the event “the student got a grade poorer than C” in terms of values of the random variable X. What is the probability of this event? <BR>\n" );
document.write( "(X < 2) ,  P(X <2 ) = P(1) + P(0) = .10 + .02 = .12 Or 12 % </SPAN>\n" );
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