Question

In: Statistics and Probability

Question 6: An English professor believes that the average grade on an English essay in a...

Question 6: An English professor believes that the average grade on an English essay in a particular school system for females is higher than for males. A random sample of 31 females had a mean score of 82 with a standard deviation of three, and a random sample of 25 males had a mean score of 76 with a standard deviation of four. Does the data agree with this professor?

a) Is this an observational study or an experiment?

b) Identify (and classify) the explanatory and response variables.

c) Summarize the information in this question into a table.

d) Create a 95 % confidence by using the statistical process. You do not have to visualize the assumptions or the data for this question.

Solutions

Expert Solution

a) Is this an observational study or an experiment?

Ans - It is an experiment as the data is collected and studied the claim.

b) Identify (and classify) the explanatory and response variables.

Ans - Response variable - average grade on an English essay in a particular school system for FEMALES

Independent Variable - average grade on an English essay in a particular school system for MALES

c) Summarize the information in this question into a table.

Ans -

Female Male
Average 82 76
SD 3 4
Sample Size 31 25

d) Create a 95 % confidence by using the statistical process. You do not have to visualize the assumptions or the data for this question.

Ans - Here we will compute the confidence interval for mean for FEMALES,

The computation is as follows

Sample size n = 31
Sample mean X̄ = 82
Sample standard deviation σ = 3
Z-score for 95% confidence level = 1.960

= 82 ± 1.96035.5678
= 82 ± 1.960 x 0.5388
= 82 ± 1.056
82 + 1.056 = 83.0561 or 82 - 1.056 = 80.9439

The lower limit is 80.9439 and
The upper limit is 83.0561


Related Solutions

A biology professor claims that, on the average, 10% of her students get a grade of...
A biology professor claims that, on the average, 10% of her students get a grade of A, 30% get a B, 40% get a C, 10% get a D, and 10% get an F. The grades of a random sample of 100 students were recorded. The following table presents the results. Grade A B C D F Observed 10 34 46 6 4 Test the hypothesis that the grades follow the distribution claimed by the professor. Use the α =...
1. A statistics professor classifies his students according to their grade point average (GPA) and their...
1. A statistics professor classifies his students according to their grade point average (GPA) and their class rank. GPA is on a 0.0 – 4.0 scale, and class rank is defined as the lower class (year 1 and year 2) and the upper class (year 3 and year 4). One student is selected at random. GPA Under 20 2.0 -3.0 over 3.0 Lower Class (Year 1 and 2) 0.05 0.20 0.10 0.35 Upper Class (Year 3 and 4) 0.10 0.35...
In a section of an English 201 class, the professor decides to be “generous” with the...
In a section of an English 201 class, the professor decides to be “generous” with the students and will grade the next exam in a unique way. Grades will be assigned according to the following rule: The top 10% receive A’s, the next 20% receive B’s, the middle 40% receive C’s, the next 20% receive D’s, and the bottom 10% receive F’s. Some may refer to this type of grading as “curving” which gave rise to the phrase, “Professor, do...
Answer the following Essential Question: Professor Terrence, from the English department at BMCC, incurred $350 dollars...
Answer the following Essential Question: Professor Terrence, from the English department at BMCC, incurred $350 dollars in educational expenses during 2019. He purchased supplies that were used by his students during the academic year. Please advice Prof. Terrence if his educational expenses qualifies as a deduction for Adjusted Gross Income (AGI)? Guiding Hints/Questions: - who qualifies for educational expenses deductions? - what is the limitations, if any? - see instructions for Form 1040
the instructor of an english course is interested if there is a difference in mean grade...
the instructor of an english course is interested if there is a difference in mean grade on the tests between 2 classes Mean 73.00 67.00 N 101 61 SD 10.50 11.00 Is there a significant difference in the average grades of these two classes? Compute the power of the findings, explaining what it means (7 grades) What is the effect size? Interpret the effect size show all work
The time for a professor to grade an exam is normally distributed with a mean of...
The time for a professor to grade an exam is normally distributed with a mean of 12.6 minutes and a standard deviation of 2.5 minutes. 1. Compute Z-score if it took the professor 15 minutes to grade an exam 2. What is the probability that a randomly selected exam will require between 12 and 15 minutes to grade? 3. What is the probability that a randomly selected exam will require less than 15 minutes to grade?
(Question 6) To test whether students in a higher grade level will be less disruptive in...
(Question 6) To test whether students in a higher grade level will be less disruptive in class, a school psychologist records the number of documented interruptions during one day of classes from nine local high schools. The sample consisted of nine (n = 9) freshman, sophomore, junior, and senior high school classes. The data for each high school class are given in the table. High School Class Freshman Sophomore Junior Senior 0 4 0 2 2 4 0 2 4...
An English professor assigns letter grades on a test according to the following scheme. A: Top...
An English professor assigns letter grades on a test according to the following scheme. A: Top 13%of scores B: Scores below the top 13% and above the bottom 61%61%6 C: Scores below the top 39% and above the bottom 22% D: Scores below the top 78% and above the bottom 6% F: Bottom 6% of scores Scores on the test are normally distributed with a mean of 75.1 and a standard deviation of 9.1. Find the numerical limits for a...
An English professor assigns letter grades on a test according to the following scheme. A: Top...
An English professor assigns letter grades on a test according to the following scheme. A: Top 15% of scores B: Scores below the top 15% and above the bottom 64% C: Scores below the top 36% and above the bottom 21% D: Scores below the top 79% and above the bottom 8% F: Bottom 8% of scores Scores on the test are normally distributed with a mean of 76.5 and a standard deviation of 8.4. Find the numerical limits for...
An English professor assigns letter grades on a test according to the following scheme. A: Top...
An English professor assigns letter grades on a test according to the following scheme. A: Top 14%14% of scores B: Scores below the top 14%14% and above the bottom 57%57% C: Scores below the top 43%43% and above the bottom 24%24% D: Scores below the top 76%76% and above the bottom 8%8% F: Bottom 8%8% of scores Scores on the test are normally distributed with a mean of 69.669.6 and a standard deviation of 99. Find the numerical limits for...
ADVERTISEMENT
ADVERTISEMENT
ADVERTISEMENT