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
DanielleElmas [232]
3 years ago
6

Suppose a 90% confidence interval for the mean salary of college graduates in a town in Mississippi is given by [$38,737, $50,46

3]. The population standard deviation used for the analysis is known to be $14,300.
a. What is the point estimate of the mean salary for all college graduates in this town?
Point estimate
b. Determine the sample size used for the analysis.
Sample size
Mathematics
1 answer:
JulsSmile [24]3 years ago
7 0

Answer:

a. The point estimate was of $44,600.

b. The sample size was of 16.

Step-by-step explanation:

Confidence interval concepts:

A confidence interval has two bounds, a lower bound and an upper bound.

A confidence interval is symmetric, which means that the point estimate used is the mid point between these two bounds, that is, the mean of the two bounds.

The margin of error is the difference between the two bounds, divided by 2.

a. What is the point estimate of the mean salary for all college graduates in this town?

Mean of the bounds, so:

(38737+50463)/2 = 44600.

The point estimate was of $44,600.

b. Determine the sample size used for the analysis.

First we need to find the margin of error, so:

M = \frac{50463-38737}{2} = 5863

Relating the margin of error with the sample size:

We have that to find our \alpha level, that is the subtraction of 1 by the confidence interval divided by 2. So:

\alpha = \frac{1 - 0.9}{2} = 0.05

Now, we have to find z in the Z-table as such z has a p-value of 1 - \alpha.

That is z with a pvalue of 1 - 0.05 = 0.95, so Z = 1.64.

Now, find the margin of error M as such

M = z\frac{\sigma}{\sqrt{n}}

In which \sigma is the standard deviation of the population and n is the size of the sample.

For this problem, we have that \sigma = 14300, M = 5863. So

M = z\frac{\sigma}{\sqrt{n}}

5863 = 1.645\frac{14300}{\sqrt{n}}

5863\sqrt{n} = 1.645*14300

\sqrt{n} = \frac{1.645*14300}{5863}

(\sqrt{n})^2 = (\frac{1.645*14300}{5863})^2

n = 16

The sample size was of 16.

You might be interested in
You pick a card at random.
katrin [286]

Answer:

The probabily of P(not less than 6) is

P= the favorable outcomes/ the total outcomes

favorable out come is 1 case(7)

the total outcomes are 5 cases(2,3,5,6)

P=1/5=20%

7 0
2 years ago
Examine the following graphed system of linear inequalities.​
AleksandrR [38]

Answer:

what do you want to be answered

Step-by-step explanation:

6 0
3 years ago
Read 2 more answers
4/16 Being Reduced Is ?
mamaluj [8]
The answer is 1/4 because all you have to really do is simplify
4 0
3 years ago
Can someone please help me
ale4655 [162]

Answer:

-4

Step-by-step explanation:

In order to get from point -1, 8, to point 2, -4, you would have to go down 12 and right 3, which would be 12/-3, which would simplify to -4

8 0
3 years ago
Read 2 more answers
PLS HURRY WILL GIVE BRAINLIEST
Bumek [7]

Answer:

brainly.com/question/16248952

Step-by-step explanation:

4 0
2 years ago
Other questions:
  • What is the result of rotating the<br>point (x, y) 90 degrees clockwise?​
    9·1 answer
  • 30 POINTS
    12·1 answer
  • What is the value of x?
    14·1 answer
  • Please help me out with this. The sides of an isosceles triangle have lengths 2x + 4 and x + 8. The base has length 5x - 2. What
    7·1 answer
  • 14 less than 8 times a number is 3 more than 4 times the number. What is the number? ​
    9·1 answer
  • Please help me, i’m stuck and confusedd..
    14·1 answer
  • A dwarf sea horse swims 3/4 inch in a minute. how many minutes would it take a seahorse to swim 1/3 of a inch?
    10·1 answer
  • 9. What is the slope of the line through the points (-2, -1) and (4, 3)?
    15·1 answer
  • Factorise the quadratic expression <br>pls help me I'll give brainliest <br>x²+8x-48​
    5·1 answer
  • Divide.<br><br><br>0.36 324<br><br><br>Enter your answer in the box.
    8·1 answer
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!