document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=195376>Question 195376</A>: <I><SPAN STYLE=\"word-break: break-all;\"> PLs hELP!!UrGENT!,,nEED youR cOOperAtion..THANK you>>\r<BR>\n" );
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document.write( "#1 problem:<BR>\n" );
document.write( "A local medical research association proposes to sponsor a footrace. The average time it takes to run the course is 45.8 minutes with a standard deviation of 36 minutes. If the association decides to include only the top 25% of the racers, what should be the cut off time in the tryout run? Assume the variable is normally distributed. Would a person who runs the course in 40 minutes qualify?\r<BR>\n" );
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document.write( "#2 problems:<BR>\n" );
document.write( "During october, the average temperature Whitman Lake is 53.2 and the standard deviation is 2.3. Assume the variable is normally distributed. For a randomly selected day in october, find the probability that the temperature will be as follows.<BR>\n" );
document.write( "a. above 54.<BR>\n" );
document.write( "b. below 60.<BR>\n" );
document.write( "c. between 49 and 55.<BR>\n" );
document.write( "d. if the lake temperature were above 60 would you call it very warm?\r<BR>\n" );
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document.write( "#3 problem:<BR>\n" );
document.write( "The average time a person spends at the Barefoot Landing Seaquarium 96 minutes. The standard deviation is 17 minutes. Assume the variable is normally distributes. if a visitor is selected at random, find the probability that he or she will spend the following time at the seaquarium.<BR>\n" );
document.write( "A. at least 120 minutes<BR>\n" );
document.write( "b. At most 80 minutes<BR>\n" );
document.write( "c. suggest a time for a bus to return to pick up a group of tourists.\r<BR>\n" );
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document.write( "#4 problem:<BR>\n" );
document.write( "The average commute to work(one way) is 25.5 minutes according to the 2000 census. If we assume that commuting times are normally distributed with a standard deviation of 6.1 minutes, what is the probability that a randomly selected commuter spends more than 30 minutes a day commuting one way?\r<BR>\n" );
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document.write( "#5 problem:<BR>\n" );
document.write( "If the average price of a new home is $145,500, find the maximum and minimum prices of the houses that a contractor will build to include the middle 80% of the market. Assume that the standard deviation of prices $1500 and the variable is normally distributed<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 #146539 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=146539\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> #1 problem:<BR>\n" );
document.write( "A local medical research association proposes to sponsor a footrace. The average time it takes to run the course is 45.8 minutes with a standard deviation of 36 minutes.<BR>\n" );
document.write( "If the association decides to include only the top 25% of the racers, what should be the cut off time in the tryout run?<BR>\n" );
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document.write( "The z that corresponds to the top 25% is 0.6745 <BR>\n" );
document.write( "Then x = z*s + u<BR>\n" );
document.write( "x = 0.6745*36 + 45.8 = 70.08 minutes (cut-off time)<BR>\n" );
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document.write( "Assume the variable is normally distributed. <BR>\n" );
document.write( "Would a person who runs the course in 40 minutes qualify? <BR>\n" );
document.write( "Ans: Absolutely<BR>\n" );
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document.write( "#2 problems:<BR>\n" );
document.write( "During october, the average temperature Whitman Lake is 53.2 and the standard deviation is 2.3. <BR>\n" );
document.write( "Assume the variable is normally distributed. For a randomly selected day in october, find the probability that the temperature will be as follows.<BR>\n" );
document.write( "a. above 54.<BR>\n" );
document.write( "b. below 60.<BR>\n" );
document.write( "c. between 49 and 55.<BR>\n" );
document.write( "d. if the lake temperature were above 60 would you call it very warm?<BR>\n" );
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document.write( "Find the z value of each of these using z = (x-u)/s<BR>\n" );
document.write( "Then find the answer to the question.<BR>\n" );
document.write( "Example <BR>\n" );
document.write( "a. above 54<BR>\n" );
document.write( "z(54) = (54-53.2)/2.3 = 0.3478<BR>\n" );
document.write( "P(temperature is above 54) = P(z > 0.3478) = 0.3640<BR>\n" );
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document.write( "#3 problem:<BR>\n" );
document.write( "The average time a person spends at the Barefoot Landing Seaquarium 96 minutes. The standard deviation is 17 minutes. Assume the variable is normally distributes. if a visitor is selected at random, find the probability that he or she will spend the following time at the seaquarium.<BR>\n" );
document.write( "A. at least 120 minutes<BR>\n" );
document.write( "b. At most 80 minutes<BR>\n" );
document.write( "c. suggest a time for a bus to return to pick up a group of tourists.<BR>\n" );
document.write( "Comment: Use the same procedure as in question #2<BR>\n" );
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document.write( "#4 problem:<BR>\n" );
document.write( "The average commute to work(one way) is 25.5 minutes according to the 2000 census. If we assume that commuting times are normally distributed with a standard deviation of 6.1 minutes, what is the probability that a randomly selected commuter spends more than 30 minutes a day commuting one way? <BR>\n" );
document.write( "#5 problem:<BR>\n" );
document.write( "If the average price of a new home is $145,500, find the maximum and minimum prices of the houses that a contractor will build to include the middle 80% of the market. Assume that the standard deviation of prices $1500 and the variable is normally <BR>\n" );
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document.write( "Comment:<BR>\n" );
document.write( "#4 and #5 are worked the same as 1-3.  Find the appropriate z score. Then<BR>\n" );
document.write( "convert to an x score using x = zs + u<BR>\n" );
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document.write( "Cheers,<BR>\n" );
document.write( "Stan H. </SPAN>\n" );
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