13. A discount retail store gives a 8% discount

The ability to find a job after graduation is very important to GSU students as it is to the students at most colleges and unive

Murrr4er [49]

Answer:

(0.806, 0.839)

Step-by-step explanation:

In a sample with a number n of people surveyed with a probability of a success of $\pi$ , and a confidence level of $1-\alpha$ , we have the following confidence interval of proportions.

$\pi \pm z\sqrt{\frac{\pi(1-\pi)}{n}}$

In which

z is the zscore that has a pvalue of $1 - \frac{\alpha}{2}$ .

Suppose we take a poll (random sample) of 3653 students classified as Juniors and find that 3005 of them believe that they will find a job immediately after graduation.

This means that $n = 3653, \pi = \frac{3005}{3653} = 0.823$

99% confidence level

So $\alpha = 0.01$ , z is the value of Z that has a pvalue of $1 - \frac{0.01}{2} = 0.995$ , so $Z = 2.575$ .

The lower limit of this interval is:

$\pi - z\sqrt{\frac{\pi(1-\pi)}{n}} = 0.823 - 2.575\sqrt{\frac{0.823*0.177}{3653}} = 0.806$

The upper limit of this interval is:

$\pi + z\sqrt{\frac{\pi(1-\pi)}{n}} = 0.823 + 2.575\sqrt{\frac{0.823*0.177}{3653}} = 0.839$

The answer is (0.806, 0.839)

5 0

3 years ago

The soccer balls manufactured at a factory have pressures that are Normally distributed, with a mean pressure of 8.7 PSI and a s

nika2105 [10]

Answer:

50%.

Step-by-step explanation:

Calculate the z scores

z score = n - m / d where n = given value , m = mean and d = standard deviation.

So for a pressure of 8.1

z1 = 8.1-8.7/02 = -3

z2 = 8.8-8.7/0,2 = 0

So from the Standard Normal Distribution tables the required percentage

= 100 - 0.00135 - 50

= 49.9999

8 0

3 years ago

Read 2 more answers

Which of the following is the solution to 3 | x-1 | ≥ 12?

ryzh [129]

hope this answer helps you dear....take care and may u have a great day ahead!

7 0

3 years ago

45 = 5(3x – 6)<br> Help me

den301095 [7]

You distribute the 5 to the 3x and 6 to get 45=15x - 30 then you add 30 to the other side to get x by itself 75 = 15x and then divide 75 by 15 to get X = 5

8 0

4 years ago

Read 2 more answers

Find the sum Sn below:

Hoochie [10]

We can write <em>S</em> as

$\displaystyle S = \sum_{k=0}^{n-1} (n-k)3^k$

and expand it as

$\displaystyle S = n \sum_{k=0}^{n-1} 3^k - \sum_{k=0}^{n-1} k\cdot3^k$

The first sum is geometric, nothing tricky:

$\displaystyle\sum_{k=0}^{n-1} 3^k = 1 + 3 + 3^2 + \cdots + 3^{n-1} \\\\ \implies 3\sum_{k=0}^{n-1} 3^k = 3 + 3^2 + 3^3 + \cdots + 3^n \\\\ \implies -2\sum_{k=0}^{n-1} 3^k = 1 - 3^n \\\\ \implies \sum_{k=0}^{n-1} 3^k = \frac{3^n-1}2$

For the second sum, you can use the same method employed in another question of yours (24494877) to find

$\displaystyle \sum_{k=0}^{n-1} k\cdot 3^k = \frac{(2n-3)3^n+3}4$

So this sum comes out to

$\displaystyle S = n\cdot\frac{3^n-1}2 - \frac{(2n-3)3^n+3}4 \\\\ S = \frac{2n\cdot3^n-2n - (2n-3)3^n-3}4 \\\\ \boxed{S = \frac{3^{n+1}-2n-3}4}$

7 0

3 years ago