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ludmilkaskok [199]
3 years ago
10

Whats 4x=28? whats the x for the answer?

Mathematics
1 answer:
Alik [6]3 years ago
5 0
76 is the answer for x.
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Trials in an experiment with a polygraph include results that include cases of wrong results and cases of correct results. Use a
hram777 [196]

Answer and Step-by-step explanation:

This is a complete question

Trials in an experiment with a polygraph include 97 results that include 23 cases of wrong results and 74 cases of correct results. Use a 0.01 significance level to test the claim that such polygraph results are correct less than 80​% of the time. Identify the null​hypothesis, alternative​ hypothesis, test​ statistic, P-value, conclusion about the null​ hypothesis, and final conclusion that addresses the original claim. Use the​ P-value method. Use the normal distribution as an approximation of the binomial distribution.

The computation is shown below:

The null and alternative hypothesis is

H_0 : p = 0.80

Ha : p < 0.80

\hat p = \frac{x}{ n} \\\\= \frac{74}{97}

= 0.7629

Now Test statistic = z

= \hat p - P0 / [\sqrtP0 \times (1 - P0 ) / n]

= 0.7629 - 0.80 / [\sqrt(0.80 \times 0.20) / 97]

= -0.91

Now

P-value = 0.1804

\alpha = 0.01

P-value > \alpha

So, it is Fail to reject the null hypothesis.

There is ample evidence to demonstrate that less than 80 percent of the time reports that these polygraph findings are accurate.

5 0
4 years ago
10
Jlenok [28]

Answer:

False

Step-by-step explanation:

3 0
3 years ago
1. Find the 90% Cl for the population mean if sample
Elden [556K]

Answer:

The answer is below

Step-by-step explanation:

1)

mean (μ) = 12, SD(σ) = 2.3, sample size (n) = 65

Given that the confidence level (c) = 90% = 0.9

α = 1 - c = 0.1

α/2 = 0.05

The z score of α/2 is the same as the z score of 0.45 (0.5 - 0.05) which is equal to 1.65

The margin of error (E) is given as:

E=Z_{\frac{\alpha}{2} }*\frac{\sigma}{\sqrt{n} } =1.65*\frac{2.3}{\sqrt{65} } =0.47

The confidence interval = μ ± E = 12 ± 0.47 = (11.53, 12.47)

2)

mean (μ) = 23, SD(σ) = 12, sample size (n) = 45

Given that the confidence level (c) = 88% = 0.88

α = 1 - c = 0.12

α/2 = 0.06

The z score of α/2 is the same as the z score of 0.44 (0.5 - 0.06) which is equal to 1.56

The margin of error (E) is given as:

E=Z_{\frac{\alpha}{2} }*\frac{\sigma}{\sqrt{n} } =1.56*\frac{12}{\sqrt{45} } =2.8

The confidence interval = μ ± E = 23 ± 2.8 = (22.2, 25.8)

8 0
3 years ago
Help
pychu [463]
Use the following formula valid fo every polyhedron. 

v-e+f=2 
<span>
Search for Euler characteristic, or Euler-Poicare characteristic for more depth about this formula </span>

v= number of vertices 

e=number of edges 

f=number of faces 

<span>You get v=13

<span>I hope my answer has come to your help. Thank you for posting your question here in </span>Brainly<span>. We hope to answer more of your questions and inquiries soon. Have a nice day ahead!</span>
</span>
3 0
3 years ago
A certain bay with very high tides displays the following behavior. In one 12-h period the water starts at mean sea level, rises
Firdavs [7]

Answer:

the required equation is; y = 21 sin(πt/6)

Step-by-step explanation:

Given the data in the question;

Water rises above sea level = 21 ft

Water drops below sea level = 21 ft

so

maximum = 21 ft and also

minimum = 21 ft

Amplitude = ( maximum + minimum ) / 2

Amplitude = ( 21 + 21 ) / 2

Amplitude = ( 21 + 21 ) / 2 = 42/2 = 21 ft

Period = 12 hours

and we know that; period = 2π/b

so

12 = 2π/b

12b = 2π

b = 2π / 12

b = π/6

Standard equation for simple harmonic is; y = asin(bt)

we substitute

y = 21 sin(πt/6)

Hence the required equation is; y = 21 sin(πt/6)

7 0
3 years ago
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