Need help with math

Assume, for the sake of this question, that the data were collected through a well-designed, well-implemented random sampling me

amid [387]

Answer:

Since the pvalue of the test is 0.2743 > 0.1, the threshold probably was met.

Step-by-step explanation:

The widget manufacturing company had established a threshold of 60% preferring the proposed new widget to move forward with producing the new widgets.

This means that at the null hypothesis we test if the proportion is at least 60%, that is:

$H_{0}: p \geq 0.6$

And the alternate hypothesis is:

$H_{a}: p < 0.6$

The test statistic is:

$z = \frac{X - \mu}{\frac{\sigma}{\sqrt{n}}}$

In which X is the sample mean, $\mu$ is the value tested at the null hypothesis, $\sigma$ is the standard deviation and n is the size of the sample.

0.6 is tested at the null hypothesis:

This means that:

$\mu = 0.6$

$\sigma = \sqrt{0.6*0.4}$

Three hundred thirty-eight of 575 respondents reported preferring the proposed new widget.

This means that $n = 575, X = \frac{338}{575} = 0.5878$

Value of the test-statistic:

$z = \frac{X - \mu}{\frac{\sigma}{\sqrt{n}}}$

$z = \frac{0.5878 - 0.6}{\frac{\sqrt{0.6*0.4}}{\sqrt{575}}}$

$z = -0.6$

Pvalue of the test and decision:

We want to find the probability of a proportion of 0.5878 or lower, which is the pvalue of z = -0.6.

Looking at the z-table, z = -0.6 has a pvalue of 0.2743.

Since 0.2743 > 0.1, the threshold probably was met.

3 0

3 years ago

Lilly bought stock at $83.60. The next day, the price increased by $15.35. Then this price changed by $-2.15.Wgat was the final

rodikova [14]

The final stock price would be $96.8

3 0

3 years ago

NEED HELP Find values for a, b, c, and d so that the following matrix product equals the 2X2 identity matrix. Explain or show ho

ehidna [41]

We want to find the values of a, b, c, and d such that the given matrix product is equal to a 2x2 identity matrix. We will solve a system of equations to find:

b = 1
a = -1
c = -2
d = -1

<h3>Presenting the equation:</h3>

Basically, we want to solve:

$\left[\begin{array}{cc}-1&2\\a&1\end{array}\right]*\left[\begin{array}{cc}b&c\\1&d\end{array}\right] = \left[\begin{array}{cc}1&0\\0&1\end{array}\right]$

The matrix product will be:

$\left[\begin{array}{cc}-b + 2&-c + 2d\\a*b + 1&a*c + d\end{array}\right]$

Then we must have:

-b + 2 = 1

This means that:

b = 2 - 1 = 1

b = 1

We also need to have:

a*b + 1 = 0

we know the value of b, so we just have:

a*1 + b = 0

a = -1

Now the two remaining equations are:

-c + 2d = 0

a*c + d = 1

Replacing the value of a we get:

-c + 2d = 0

-c + d = 1

Isolating c in the first equation we get:

c = 2d

Replacing that in the other equation we get:

-(2d) + d = 1

-d = 1

d = -1

Then:

c = 2d = 2*(-1) = -2

c = -2

So the values are:

b = 1
a = -1
c = -2
d = -1

If you want to learn more about systems of equations, you can read:

brainly.com/question/13729904

4 0

3 years ago

Fatima needs at least $20 to buy a purse. She

Kitty [74]

Answer:

Fatima will nee to sell 10 cookies.

Step-by-step explanation:

6 0

3 years ago

Read 2 more answers

What point is the center of dilation

igor_vitrenko [27]

Answer:

The answer is C/Point E

Step-by-step explanation:

I did the test.

4 0

3 years ago

Read 2 more answers

Need help with math​

Need help with math