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3 years ago

14

Suppose that administrators at a large urban high school want to gain a better understanding of the prevalence of bullying withi

n their school. They select a random sample of 240 students who are asked to complete a survey anonymously. Of these students, 54 report that they have experienced bullying. Use this information to find a 95% ???? ‑confidence interval for ???? , the true proportion of students at this school who have experienced bullying.

1 answer:

RSB [31]3 years ago

8 0

Answer: $(0.273,\ 0.783)$

Step-by-step explanation:

Given : Total number of students who are asked to complete a survey anonymously : n= 240

Number of students

The proportion report that they have experienced bullying =54

Then , the proportion that students have experienced bullying = $p=\dfrac{54}{240}=0.225$

Significance interval : $\alpha=1-0.95=0.05$

Critical value : $z_{\alpha/2}=1.96$

The confidence interval for the true proportion is given by :-

$p\pm z_{\alpha/2}\sqrt{\dfrac{p(1-p)}{n}}\\\\=0.225\pm (1.96)\sqrt{\dfrac{(0.225)(1-0.225)}{240}}\\\\\approx0.225\pm0.0528\\\\=(0.255-0.528,\ 0.255+0.528)\\\\=(0.273,\ 0.783)$

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lord [1]

Answer:

45% probability that a randomly selected customer saw the advertisement on the internet or on television

Step-by-step explanation:

We solve this problem building the Venn's diagram of these probabilities.

I am going to say that:

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By the same logic, we have that:

$B = b + (A \cap B)$

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6 0

3 years ago

What is the missing addend?<br> 52,835 +<br> = 87,216

posledela

Answer: 34,381

Step-by-step explanation:

You have to subtract 52,835 by the sum 87,216 which will get you the answer of 34,381

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n a call center the number of received calls in a day can be modeledby a Poisson random variable. We know that, on average, 0.5%

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Step-byy-step explanation:

Let N be the number of received calls in a day

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AURORKA [14]

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$\cos \left(\frac{\pi }{4}\right)=\frac{\sqrt{2}}{2}$

$\sin \left(\frac{\pi }{4}\right)=\frac{\sqrt{2}}{2}$

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On simplifying, we get

$Z_1* Z_2 =-3\sqrt{2}$

<h2>Therefore, correct option is 1st option.</h2>

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3 years ago

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kifflom [539]

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