• 100% Satisfaction Guarantee
SusanAthena, Master's Degree
Category: Calculus and Above
Satisfied Customers: 102
Experience:  Tutor for Algebra, Geometry, Statistics. Explaining math in plain English.
12809769
Type Your Calculus and Above Question Here...
SusanAthena is online now

# 1. a. Occasionally students ask if I “grade on a curve”. By

### Customer Question

1. a. Occasionally students ask if I “grade on a curve”. By this they usually mean, do I add extra points to everyone’s test scores if the whole class does poorly. The phrase “grading on a curve” really means to assign grades based on a normal distribution.Assume I give a test with a mean score of 81 and a standard deviation of 12.Draw a sketch of a normal distribution centered at the mean of 81 and divide it into 5 regions based on the following grades:
The top 15% of scores receive an A
The next 20% of scores receive a B
The middle 30% of scores receive a C
The next 20% of scores receive a D
The bottom 15% of scores receive an Fa. Find the minimum scores on the test that would give a student an A, B, C and D. There is no “lowest” F other than 0.
(You do not have to include your picture in your answer document, just send me the lowest test score needed for an A, lowest test score needed for a B, lowest score for a C and lowest score for a D, along with all calculations that you used or a description of your technology commands)b. Repeat the procedure from part a with a test having a mean of 71 and a standard deviation of 15.c. Have you ever had a class or an assignment that was graded this way? What do you see as the advantages and disadvantages of this system? Would you want to be “graded on a curve” based on a normal distribution?
- Yes, I have. I think some of the advantages are if you are one of the people who scored low you have a chance to have your score increase. I actually like being graded on a curve.2. Too much cholesterol in the blood can increase the risk of heart disease.Young women are generally less afflicted with high cholesterol than other groups. The cholesterol levels for women aged 20-34 follow an approximately normal distribution with mean 185 milligrams per deciliter (mg/dL) and standard deviation 39 mg/dL.Middle-aged men are more susceptible to high cholesterol. The cholesterol levels of men aged 55-64 are approximately normal with mean 222 mg/dL and standard deviation 37 mg/dL.Cholesterol levels above 240 mg/dL demand medical attention.a. What percentage of women aged 20-34 have levels above 240 mg/dL?b. What percentage of men 55-64 have levels above 240 mg/dL?Cholesterol levels from 200 -240 are considered borderline high.c. What percentage of women aged 20-34 have levels between 200 and 240 mg/dL?d. What percentage of men 55-64 have levels between 200 and 240 mg/dL?
Customer: no
Submitted: 11 months ago.
Category: Calculus and Above
Expert:  Mr. Glenn replied 11 months ago.

Hi