A survey was conducted among people who visit swimming pools. 209 people were asked about the preferences in water sanitizing. 112 respondents reported they prefer pools with mechanical methods of water sanitizing, and 97 respondents reported they do not have any preferences. Construct a test for a difference in proportions for this survey to find out if the proportion of people who prefer mechanical methods of water sanitizing truly exceeds the proportion of people who have no sanitizing methods preferences, if it is possible. A :

The claim that needs to be tested is that the proportion of people who prefer mechanical methods of water sanitizing truly exceeds the proportion of people who have no sanitizing methods preferences. This can be expressed as the population proportion of people who prefer mechanical methods of water sanitizing is significantly higher than 0.5.

This is a hypothesis test for a  population proportion.

The test will have null and alternative hypothesis:

Test statistic z = 0.972

P-value = 0.166

At a significance level of 0.05, there is not enough evidence to support the claim that the proportion of people who prefer mechanical methods of water sanitizing truly exceeds the proportion of people who have no sanitizing methods preferences.

Step-by-step explanation:

We have to construct a hypothesis test for the population proportion. We need to test the claim that the proportion of people who prefer mechanical methods of water sanitizing truly exceeds the proportion of people who have no sanitizing methods preferences.

As the survey is done as a yes/no question, the null hypothesis would state that the amount of people who prefer mechanical methods of water sanitizing is not significantly different from the proportion of people who have no sanitizing methods preferences. That can be expressed as the population proportion equals 0.5, so both proportions are equal.

The alternative hypothesis would state that the proportion of people who prefer mechanical methods of water sanitizing truly exceeds the proportion of people who have no sanitizing methods preferences. This could be expressed as the population proportion significantly bigger than 0.5.

Then, the null and alternative hypothesis are written:

The significance level is assumed to be 0.05.

The sample has a size n=209.

The sample proportion is p=0.536.

The standard error of the proportion is:

Then, we can calculate the z-statistic as:

This test is a right-tailed test, so the P-value for this test is calculated as:

As the P-value (0.166) is greater than the significance level (0.05), the effect is  not significant.

The null hypothesis failed to be rejected.

There is not enough evidence to support the claim that the proportion of people who prefer mechanical methods of water sanitizing truly exceeds the proportion of people who have no sanitizing methods preferences.

this story was prepared by jim

mccullaugh in los angeles and

al stewart in new york.

new york the colossal success of "top gun" appears to have dramatically altered madison avenue's

perception of corporate sponsorship

of home video projects.

the paramount home video re- lease, featuring a 60- second diet

pepsi spot, was by no means the

first prerecorded video to carry an advertiser's plug, but it was the

first major theatrical release to do so. in the aftermath of the title's

success, paramount is widely ex- pected to ink a similar deal for

"crocodile dundee" or "star trek

iv" or both.

corporate america's new attraccds push british

recording sales

to 19% gain

london fueled by the compact

disk boom, the value of u.k. manu- facturer shipments of recordings

rose 19% in the 12 -month period ended march 1987, according to the

british phonographic industry.

total value of u.k. shipments for

the period was $755 million for all

configurations. (all value figures

are based on an exchange rate of

$1.68 to the pound sterling.)

cd sales totaled 10.7 million units

worth $121.3 million- compared

with 3.7 million units worth $39.5

million in the prior 12 months -and

accounted for two -thirds of the

overall gain in trade value. at present growth rates, says the bpi, cd

sales for calendar 1987 will reach 20

(continued on page 79)

step-by-step explanation:

6.9

step-by-step explanation:

simple math really

6 1/2 times 0.6 = 3.9

but if you are just doing 6 and not 6 1/2 then the answer is 3.6