Chose the step below that correctly uses the distributive property to begin solving the equation:

DanielleElmas [232]

Answer:

The 95% confidence interval for the true percentage of all adults over 30 who shop at that mall who admit to having lost their car at the mall is (25.37%, 43.93%).

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 z-score that has a p-value of $1 - \frac{\alpha}{2}$ .

Of 101 randomly selected adults over 30 who frequent a very large mall, 35 admitted to having lost their car at the mall.

This means that $n = 101, \pi = \frac{35}{101} = 0.3465$

95% confidence level

So $\alpha = 0.05$ , z is the value of Z that has a p-value of $1 - \frac{0.05}{2} = 0.975$ , so $Z = 1.96$ .

The lower limit of this interval is:

$\pi - z\sqrt{\frac{\pi(1-\pi)}{n}} = 0.3465 - 1.96\sqrt{\frac{0.3465*0.6535}{101}} = 0.2537$

The upper limit of this interval is:

$\pi + z\sqrt{\frac{\pi(1-\pi)}{n}} = 0.3465 + 1.96\sqrt{\frac{0.3465*0.6535}{101}} = 0.4393$

As percentages:

0.2537*100% = 25.37%

0.4393*100% = 43.93%

The 95% confidence interval for the true percentage of all adults over 30 who shop at that mall who admit to having lost their car at the mall is (25.37%, 43.93%).

4 0

2 years ago

Graph the function f(x)=4x^2

alina1380 [7]

Answer:

Step-by-step explanation:

6 0

4 years ago

Read 2 more answers

Y = −1 / 4 (x + 4) 2 −1 on a coordinate plane using its vertex, focus, and directrix.

trasher [3.6K]

Answer:

Hello,

Step-by-step explanation:

do I remind you of the formula :

where (a,b) is the vertex and y=k the directrix

$y=\dfrac{(x-a)^2}{2(b-k)} +\dfrac{b+k}{2} \\\\\\y=-\dfrac{(x+4)^2}{4} -1 \\\\Using\ identification:\\a=-4\\2(b-k)=-4\\b+k=-2\\\\\left\{\begin{array}{ccc}b-k&=&-2\\b+k&=&-2\\\end{array}\right.\\\\\\\left\{\begin{array}{ccc}2b&=&-4\\2k&=&0\\\end{array}\right.\\\\\\\left\{\begin{array}{ccc}b&=&-2\\k&=&0\\\end{array}\right.\\$