The writer is very fast, professional and responded to the review request fast also. Thank you.
1. Someone has sketched one block of a family-income histogram. About what percentage of families in this district had incomes between $60,000 and $75,000 a year?
2 % per $1,000
50 100
Family Income (in $1,000)
(10 points)
2. In a large lecture course, the scores on the final examination followed the normal curve closely. The average score was 50 points and three fourths of the class scored between 40 and 60 points. The SD of the scores was
(i) large than 10 points
(i) smaller than 10 points
(iii) impossible to say with the information given.
(15 points)
3. The weight of a certain group of men follow the normal curve, with an average of 160 pounds and an SD of 30 pounds. Fill in the blanks; explain briefly.
a. A man who weighed 120 pounds was at the ________percentile of the weight distribution.
b. To be at the 80th percentile of the distribution, a man needed to weight about _________ pounds
c. About what percentage of these men weigh between 180 pounds and 200 pounds?
(20 points)
4. Given the following data set:
x |
1 |
3 |
7 |
9 |
13 |
15 |
y |
1 |
5 |
8 |
10 |
11 |
13 |
a. Find the correlation coefficient.
b. Using this to predict the value of y when x = 2.
c. Find the root mean square error.
(20 points)
5. For 1000 men age 18 – 24 in the HANES sample
Average height (X) = 70 inches SDx = 3 inches
Average weight (Y) = 162 pounds SDy = 30 pounds
Correlation r = .6
One man in the sample was 63 inches tall what is his expected weight?
(15 points)
6. In a certain class, midterm score average out 60 with an SD of 15, as do scores on the final. The correlation between midterm scores and final scores is about 0.50.the scatter diagram is football-shaped.
a. Predict the final score for a student whose midterm score is
(i) 75 (ii) 30 (ii) 60 (iv) unknown
b. Predict the midterm score for a student whose final score is 45.
c. Apparently low-scoring students on the midterm do better on the final, but low –
scoring student on the final did better on the midterm. How is this possible?
(20 points)
Delivering a high-quality product at a reasonable price is not enough anymore.
That’s why we have developed 5 beneficial guarantees that will make your experience with our service enjoyable, easy, and safe.
You have to be 100% sure of the quality of your product to give a money-back guarantee. This describes us perfectly. Make sure that this guarantee is totally transparent.
Read moreEach paper is composed from scratch, according to your instructions. It is then checked by our plagiarism-detection software. There is no gap where plagiarism could squeeze in.
Read moreThanks to our free revisions, there is no way for you to be unsatisfied. We will work on your paper until you are completely happy with the result.
Read moreYour email is safe, as we store it according to international data protection rules. Your bank details are secure, as we use only reliable payment systems.
Read moreBy sending us your money, you buy the service we provide. Check out our terms and conditions if you prefer business talks to be laid out in official language.
Read more