237 devided by 8 times 564

The manager of a grocery store has taken a random sample of 100 customers. The average length of time it took the customers in t

andreyandreev [35.5K]

Answer:

The test statistic is c. 2.00

The p-value is a. 0.0456

At the 5% level, you b. reject the null hypothesis

Step-by-step explanation:

We want to test to determine whether or not the mean waiting time of all customers is significantly different than 3 minutes.

This means that the mean and the alternate hypothesis are:

Null: $H_{0} = 3$

Alternate: $H_{a} = 3$

The test-statistic is given by:

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

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.

Sample of 100 customers.

This means that $n = 100$

3 tested at the null hypothesis

This means that $\mu = 3$

The average length of time it took the customers in the sample to check out was 3.1 minutes.

This means that $X = 3.1$

The population standard deviation is known at 0.5 minutes.

This means that $\sigma = 0.5$

Value of the test-statistic:

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

$z = \frac{3.1 - 3}{\frac{0.5}{\sqrt{100}}}$

$z = 2$

The test statistic is z = 2.

The p-value is

Mean different than 3, so the pvalue is 2 multiplied by 1 subtracted by the pvalue of Z when z = 2.

z = 2 has a pvalue of 0.9772

2*(1 - 0.9772) = 2*0.0228 = 0.0456

At the 5% level

0.0456 < 0.05, which means that the null hypothesis is rejected.

7 0

3 years ago

Mr. Alvarez makes a walkway out of 3 cement slabs. He uses 14 cubie feet of cement to make the walkway. Each square slab has a v

AysviL [449]

Answer:

Step-by-step explanation:

answer volume cubic centimetre priority

volume=4+4=8

14-8=

6 cubic feet. 

thanx

mark as brainlest

6 0

3 years ago

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Find the volume of the largest rectangular box in the first octant with three faces in the coordinate planes and one vertex in t

makkiz [27]

Answer:

Step-by-step explanation:

$x + 2y + 3z = 12$

$z=\frac{12-x-2y}{3}$

Volume = $V=f(x,y) = xy(\frac{12-x-2y}{3} )$

find partial derivatives using product rule

$f_x =\frac{y}{3} (12-2x-2y)\\f_y = \frac{x}{3} (12-x-4y)$

i.e.

Using maximum for partial derivatives, we equate first partial derivative to 0.

y=0 or x+y =6

x=0 or x+4y =12

Simplify to get y =2, x = 4

thus critical points are (4,2) (6,0) (0,3)

Of these D the II derivative test gives

D<0 only for (4,2)

Hence maximum volume is when x=4, y=2, z= 4/3

Max volume is = 4(2)(4/3) = 32/3

6 0

2 years ago

I don't know what to do

RUDIKE [14]

Just do what is says to do i can answer it for u but im not sure if it will be correct
i have did this problem before tho

6 0

3 years ago

Write as a mixed number 1 23/24

Mnenie [13.5K]

Hi there,

This is simple 1 23/24 as a mixed number is exactly that. It has a whole which is the 1 and then 23/24 parts of another whole, therefore, the mixed number is indeed 1 23/24.

Hope this helps!

3 0

3 years ago

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