Solve 0=x2+6x+13 by completing the square.

Suppose a marketing company wants to determine the current proportion of customers who click on ads on their smartphones. It was

andrezito [222]

Answer:

The 92% confidence interval for the true proportion of customers who click on ads on their smartphones is (0.3336, 0.5064).

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 $1 - \frac{\alpha}{2}$ .

For this problem, we have that:

$n = 100, p = 0.42$

92% confidence level

So $\alpha = 0.08$ , z is the value of Z that has a pvalue of $1 - \frac{0.08}{2} = 0.96$ , so $Z = 1.75$ .

The lower limit of this interval is:

$\pi - z\sqrt{\frac{\pi(1-\pi)}{n}} = 0.42 - 1.75\sqrt{\frac{0.42*0.58}{100}} = 0.3336$

The upper limit of this interval is:

$\pi + z\sqrt{\frac{\pi(1-\pi)}{n}} = 0.42 - 1.75\sqrt{\frac{0.42*0.58}{100}} = 0.5064$

The 92% confidence interval for the true proportion of customers who click on ads on their smartphones is (0.3336, 0.5064).

4 0

4 years ago

Which expression is eq to (125^2/125^4/3)

sweet [91]

Answer:

25

Step-by-step explanation:

So the denominator can be simplified to 5⁴ → $(5^3)^\frac{4}{3}$ and then the 3's cancel out and we are left with 5⁴

Now our new fraction is $\frac{125^{2} }{5^{4} } = \frac{15625}{625}$ which then simplifies to 25

5 0

3 years ago

Find the area of the triangle with the following coordinates. A (-5,9) B (1,-7) C (8,4)

Virty [35]

QUESTION : > FIND THE ARE OF THE TRIANGLE WITH THE FOLLOWING COORDINATES.

A. (-5,9)

B . (1,-7)

C . (8,4)

ANSWER :> A.

 (-5,9). 

HOPE IT HELPS

 THANK ME LATER. 

<h2>#CARY ON LEARNING </h2>

4 0

2 years ago

What is the value of x in the inequality

GalinKa [24]

Answer & Step-by-step explanation:

Question 18

Isolate the variable by dividing each side by factors that don't contain the variable.

Inequality Form: x ≤ −10

Interval Notation: (−∞ , −10]

Question 19

Isolate the variable by dividing each side by factors that don't contain the variable.

Inequality Form: x ≤ 4

Interval Notation: (−∞ , 4]

8 0

3 years ago

16. You found a shortcut to school that saves 5 minutes off of taking the freeway. About 1 in every 10 trips

kykrilka [37]

Answer:

it saves 2.5 minutes

Step-by-step explanation:

The expected value of a random variable is the sum of products of possibilities and the probability of each.

Here, you have a probability of 0.9 of saving 5 minutes, and a probability of 0.1 of adding 20 minutes.

__

The expected value of the shortcut is ...

0.9(-5) +0.1(20) = -4.5 +2.0 = -2.5

The shortcut is expected to save 2.5 minutes on average.

_____

Additional comment

The probability of 0.9 comes from the 9 of 10 trips that result in a time saving.

6 0

2 years ago