1answer.
Ask question
Login Signup
Ask question
All categories
  • English
  • Mathematics
  • Social Studies
  • Business
  • History
  • Health
  • Geography
  • Biology
  • Physics
  • Chemistry
  • Computers and Technology
  • Arts
  • World Languages
  • Spanish
  • French
  • German
  • Advanced Placement (AP)
  • SAT
  • Medicine
  • Law
  • Engineering
IRINA_888 [86]
3 years ago
7

A college job placement office collected data about students’ GPAs and the salaries they earned in their first jobs after gradua

tion. The mean GPA was 2.9 with a standard deviation of 0.4. Starting salaries had a mean of $47200 with a SD of $8500. The correlation between the two variables was r = 0.72. The association appeared to be linear in the scatterplot. a) Write an equation of the model that can predict salary based on GPA and find the slope and intercept. b) Your brother just graduated from that college with a GPA of 3.30. He tells you that based on this model the residual for his pay is -$1880. What salary is he earning? c) What proportion of the variation in salaries is explained by variation in GPA?
Mathematics
1 answer:
frez [133]3 years ago
8 0

Answer:

X is the GPA

Y is the Salary

Standard deviation of X is 0.4

Standard deviation of Y is 8500

E(X)=2.9

E(Y)=47200

We are given that The correlation between the two variables was r = 0.72

a)y = a+bx

b = \frac{\sum(x_i-\bar{x})(y_i-\bar{y})}{\sum(x_i-\bar{x})^2} = \frac{r \times \sqrt{var(X) \times Var(Y)}}{Var(X)} =  \frac{0.72 \times \sqrt{0.4^2 \times 8500^2}}{0.4^2} = 15300

a=y-bx = 47200-(15300 \times 29) = 2830

So, slope =  15300

Intercept =  2830

So, equation : y = 2830+15300x

b) Your brother just graduated from that college with a GPA of 3.30. He tells you that based on this model the residual for his pay is -$1880. What salary is he earning?

y = 2830+15300 \times 3.3 = 53320

Observed salary = Residual + predicted = -1860+53320 = 51440

c)) What proportion of the variation in salaries is explained by variation in GPA?

The proportion of the variation in salaries is explained by variation in GPA = r^2 = (0.72)^2 =0.5184

You might be interested in
The $3.50 chocolate bar I purchased was on sale for 25% off, what did I pay for it?
Alla [95]
I think it was for 2.33 cents??
7 0
3 years ago
Read 2 more answers
A theater charges $50 per ticket for seats in section a, $40 per ticket for seats in section b, and $20 per ticket for seats in
alukav5142 [94]
The first thing we must do for this case is to define variables.
 We have then:
 x: ticket for seats in section a
 y: ticket for seats in section b
 z: ticket for seats in section c
 We write the system of equations:
 50x + 40y + 20z = 335000
 x + y + z = 9500
 y = x + z + 500
 Solving the system we have:
 x = 1500
 y = 5000
 z = 3000
 Answer:
 ticket for seats in section a = 1500
 ticket for seats in section b = 5000
 
ticket for seats in section c = 3000
7 0
3 years ago
Which of the following is the equation of a vertical line
Charra [1.4K]
The correct answer is D!!
4 0
3 years ago
Help please !! .......
UkoKoshka [18]
The answer is a. congruent - sas
4 0
3 years ago
How do you write 0.67 as a percent?
KatRina [158]
Answer: 67%

67% = 0.67 percent

Other examples =

0.08 = 8 %

0.067 = 6.7%
7 0
3 years ago
Read 2 more answers
Other questions:
  • ​it's believed that as many as 2222​% of adults over 50 never graduated from high school. we wish to see if this percentage is t
    13·1 answer
  • Brainly a garden has width 13−−√ and length 713−−√. what is the perimeter of the garden in simplest radical form?
    12·2 answers
  • A circle with a radius of 1 unit​
    5·1 answer
  • 5x + 2 (x+7) =14x - 7
    11·1 answer
  • Help please. I think it's B but not sure.
    6·1 answer
  • What is the sum of 4/6 and 4/9
    9·2 answers
  • What is the measure of angle TMS? Pls explain your answer and I will mark brainliest!
    10·1 answer
  • What is the value of x in the equation below?
    5·1 answer
  • In the United States, we measure milk by the gallon. If we were using the metric system, what metric unit would we use
    9·1 answer
  • What is the measure of the base of the rectangle if the area of the triangle is 32ft^2?
    15·1 answer
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!