Change to a percent rounded to the nearest hundredth of a percent if necessary. 1 1/4, 3/5, 5/8, 1/3, 2/7

In a study of cell phone usage and brain hemispheric dominance, an Internet survey was e-mailed to 6977subjects randomly selec

kirza4 [7]

Answer:

Given :An Internet survey was e-mailed to 6977 subjects randomly selected from an online group involved with ears. There were 1337 surveys returned.

To Find : Use a 0.01 significance level to test the claim that the return rate is less than 20%.

Solution:

n = 6977

x = 1337

We will use one sample proportion test

$\widehat{p}=\frac{x}{n}$

$\widehat{p}=\frac{1334}{6977}$

$\widehat{p}=0.1911$

We are given that the claim is the return rate is less than 20%.

$H_0:p=0.2\\H_a:p$

Formula of test statistic = $\frac{\widehat{p}-p}{\sqrt{\frac{p(1-p)}{n}}}$

= $\frac{0.1911-0.2}{\sqrt{\frac{0.2(1-0.2)}{6977}}}$

= $−1.858$

Refer the z table

P(z<-1.85)=0.0332

Significance level = 0.01=α

Since p value > α

So, we accept the null hypothesis .

So,the claim that the return rate is less than 20% is false.

7 0

3 years ago

A store has x number of shirts. Each shirt was sold for $16, but the last dozen was sold on sale for $14 each. When all shirts w

Helen [10]

Answer:

28 shirts

Step-by-step explanation:

Let's see what we are given.

there are x amount of shirts ($616 total)

there are 12 in a dozen

the regular shirts are $16

the last 12 shirts are $14

Lets make an equation.

616= 14(12) + 16x

616=168+16x

448=16x

x=28

(Sorry if this explanation is bad)

5 0

3 years ago

URGENT! PLEASE HELP!

valina [46]

If your teacher is asking "which of the following can be used to prove the triangles congruent?" then I agree with your statement that it's "none of the above". We simply don't have enough information to determine if the triangles are congruent or not. If we wanted to use SAS, then we'd have to know if EB = BD was true. If we wanted ASA, then we'd have to know that A = C. If we wanted AAS, then we'd have to know that E = D.

In short, you have the correct answer. Nice work.

4 0

3 years ago

A pollster obtains a list of all the residential addresses in a certain town, and uses a random number generator to choose of th

juin [17]

Answer: Cluster Sampling

Step-by-step explanation: Sampling is the process of collecting a representative of a particular Population of persons, activities, materials etc in order to use them for an experiment or research. Sampling can be done in different ways which include Cluster Sampling, random Sampling, stratified Sampling etc.

The activities of the Pollster using a random number to choose the residents of a given location is a Sampling method by Clustering.

Cluster Sampling is the process of identifying the cluster of participants representing the population and their inclusion in the sample group.

7 0

3 years ago

Maria looked at the nutrition labels for 5 different foods. She recorded the total calories and the calories from fat for each f

Nikolay [14]

Answer:

food 1 food 3 food 5

Step-by-step explanation:

3 0

3 years ago