Need help with this question

A poll asked 1057 American adults if they believe there was a conspiracy in the assassination of President Kennedy, and found th

AVprozaik [17]

Answer:

The 95% confidence interval of the proportion of Americans who believe in the conspiracy is $0.551< p < 0.610$

Step-by-step explanation:

From the question we are told that

The sample size is n =1057

The number that believe there was a conspiracy is k = 614

Generally the sample proportion is mathematically represented as

$\^ p = \frac{614}{1057 }$

=> $\^ p = 0.5809$

From the question we are told the confidence level is 95% , hence the level of significance is

$\alpha = (100 - 95 ) \%$

=> $\alpha = 0.05$

Generally from the normal distribution table the critical value of $\frac{\alpha }{2}$ is

$Z_{\frac{\alpha }{2} } = 1.96$

Generally the margin of error is mathematically represented as

$E = Z_{\frac{\alpha }{2} } * \sqrt{\frac{\^ p (1- \^ p)}{n} }$

=> $E = 1.96 * \sqrt{\frac{0.5809 (1- 0.5809)}{1057} }$

=> $E = 0.02975$

Generally 95% confidence interval is mathematically represented as

$\^ p -E < p < \^ p +E$

=> $0.5809 - 0.02975< p < 0.5809 + 0.02975$

=> $0.551< p < 0.610$

4 0

3 years ago

According to an article in Newsweek, the natural ratio of girls to boys is 100:105. In China, the birth ratio is 100:114 (46.7%

mojhsa [17]

Answer:

$z=\frac{0.42 -0.467}{\sqrt{\frac{0.467(1-0.467)}{150}}}=-1.154$

$p_v =2*P(z$

So the p value obtained was a very high value and using the significance level given $\alpha=0.05$ we have $p_v>\alpha$ so we can conclude that we have enough evidence to FAIL to reject the null hypothesis, and we can said that at 5% of significance the proportion of girls born is not significantly different from 0.467

Step-by-step explanation:

Data given and notation

n=150 represent the random sample taken

X=63 represent the number of girls born

$\hat p=\frac{63}{150}=0.42$ estimated proportion of girls born

$p_o=0.467$ is the value that we want to test

$\alpha=0.05$ represent the significance level

Confidence=95% or 0.95

z would represent the statistic (variable of interest)

$p_v$ represent the p value (variable of interest)

Concepts and formulas to use

We need to conduct a hypothesis in order to test the claim that the true proportion if girls is 0.467.:

Null hypothesis: $p=0.467$

Alternative hypothesis: $p \neq 0.467$

When we conduct a proportion test we need to use the z statistic, and the is given by:

$z=\frac{\hat p -p_o}{\sqrt{\frac{p_o (1-p_o)}{n}}}$ (1)

The One-Sample Proportion Test is used to assess whether a population proportion $\hat p$ is significantly different from a hypothesized value $p_o$ .

Calculate the statistic

Since we have all the info requires we can replace in formula (1) like this:

$z=\frac{0.42 -0.467}{\sqrt{\frac{0.467(1-0.467)}{150}}}=-1.154$

Statistical decision

It's important to refresh the p value method or p value approach . "This method is about determining "likely" or "unlikely" by determining the probability assuming the null hypothesis were true of observing a more extreme test statistic in the direction of the alternative hypothesis than the one observed". Or in other words is just a method to have an statistical decision to fail to reject or reject the null hypothesis.

The significance level provided $\alpha=0.05$ . The next step would be calculate the p value for this test.

Since is a bilateral test the p value would be:

$p_v =2*P(z$

So the p value obtained was a very high value and using the significance level given $\alpha=0.05$ we have $p_v>\alpha$ so we can conclude that we have enough evidence to FAIL to reject the null hypothesis, and we can said that at 5% of significance the proportion of girls born is not significantly different from 0.467

3 0

3 years ago

When the expression 3x^4+5x-6x^2+10x^3 is written with terms in descending order (from highest to lowest), which list represents

san4es73 [151]

3x^4 + 5x - 6x^2 + 10x^3....in descending order

3x^4 + 10x^3 - 6x^2 + 5x
coefficients are : 3,10,-6,5

8 0

3 years ago

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Solving Inequality's

devlian [24]

How can I send you the drawn representation on number line ?

25)

z + 4 >= 2z

-z >= -4

z <= 4 (you flip the sign when you divide over negative number)

on number line: from 4 to -infinity

you use normal arithmetic like equations

29)

-9 + 2a < 3a

-9 < a (just one step done)

on number line from -9 to infinity

41 and 43 ? not in the page

5 0

3 years ago

Could someone help me with this math question? its operations with scientific notations

JulijaS [17]

Answer: 16312.5

Step-by-step explanation:

That took a lot of time. There you go.

7 0

3 years ago

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