Suppose that a standardized biology exam has a mean score of 80% correct, with a standard deviation of 3. The school administration believes that the new class of freshmen have a different mean exam score. A sample of 65 students from the freshmen class is used and a mean score of 76% correct is obtained.
Calculate a 99% confidence interval. List the lower bound (rounded to 2 decimal places) and the upper bound (rounded to 2 decimal places).

Answers

Answer 1

Answer:

The 99% confidence interval is between 62.36%(lower bound) and 89.64%(upper bound).

Step-by-step explanation:

In a sample with a number n of people surveyed with a probability of a success of [tex]\pi[/tex], and a confidence level of [tex]1-\alpha[/tex], we have the following confidence interval of proportions.

[tex]\pi \pm z\sqrt{\frac{\pi(1-\pi)}{n}}[/tex]

In which

z is the zscore that has a pvalue of [tex]1 - \frac{\alpha}{2}[/tex].

A sample of 65 students from the freshmen class is used and a mean score of 76% correct is obtained.

This means that [tex]n = 65, \pi = 0.76[/tex]

99% confidence level

So [tex]\alpha = 0.005[/tex], z is the value of Z that has a pvalue of [tex]1 - \frac{0.005}{2} = 0.995[/tex], so [tex]Z = 2.575[/tex].

The lower limit of this interval is:

[tex]\pi - z\sqrt{\frac{\pi(1-\pi)}{n}} = 0.76 - 2.575\sqrt{\frac{0.76*0.24}{65}} = 0.6236[/tex]

The upper limit of this interval is:

[tex]\pi + z\sqrt{\frac{\pi(1-\pi)}{n}} = 0.76 + 2.575\sqrt{\frac{0.76*0.24}{65}} = 0.8964[/tex]

0.6236*100 = 62.36%

0.8964*100 = 89.64%

The 99% confidence interval is between 62.36%(lower bound) and 89.64%(upper bound).


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Step-by-step explanation: because I don’t know

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Answers

Answer:

x = -156

Step-by-step explanation:

Solve for x by simplifying both sides of the equation, then isolating the variable.

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Step-by-step explanation: −x/6 +6=32

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Answer is in the file below

tinyurl.com/wpazsebu

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Answers

Answer:

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Answers

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Answers

The answer would be D every 1 inch would equal 6.66666667 added so 26.66666667

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Answers

Answer:

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Answers

Answer:

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Step-by-step explanation:

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Answers

Step-by-step explanation:

Here we are going to use the Pythagoras theorem to get the Hight of the Television

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X Being the unknown side

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Answers

Answer:

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Step-by-step explanation:

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Answers

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Answer:

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Step-by-step explanation:

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Answer:

Step-by-step explanation:

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Answer:

where?????????????????????:/

Answer:

i would but where it is?

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Answers

Answer:

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Step-by-step explanation:

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ps.

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Answers

the answer

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Answers

Answer:

The difference in elevation between Laguna del Carbon and El Alto is 12,656 feet.

Step-by-step explanation:

Given that Laguna del carbon, a salt lake located in Argentina, lies 344 feet below sea level, while El Alto, Bolivia, is located approximately 13,000 feet above sea level, to determine what is the difference in elevation between Laguna del Carbon and El Alto, the following calculation must be performed:

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Answers

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Answers

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c с
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effective than the soap solution in reducing
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Answers

Answer: group A: The organic drain cleaners claim to be more effective than the soap solution is reducing the development of clogs is false.

group B: The organic drain cleaners claim to

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group C: There is not enough information to invalidate the claim of the organic drain cleaner

Step-by-step explanation:

plato/edmentum

Answer:

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Step-by-step explanation:

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Answers

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