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PilotLPTM [1.2K]

2 years ago

14

If the measure of arc EF=47 and the measure of angle ACD=55, determine the measure of angle ECF. I really need help with this, t

hank you!!

1 answer:

djyliett [7]2 years ago

5 0

Answer:

55°

Step-by-step explanation:

∠ECF is a vertical angle with ∠ACD, so has the same measure, 55°.

_____

Whatever arc may exist between points E and F is not shown on your diagram, nor is the center (or radius) of it shown. The measure of arc EF is irrelevant to the question.

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30 points if I had 125 quarter how much money I would have

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a circle with a radius of 1 cm sits inside a 3cm x 3cm rectangle. What is the area of the shaded region (the rectangle is shaded

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3 years ago

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What is the equation of the graph

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Step-by-step explanation:

The graph you see there is called a parabola. The general equation for the graph is as below

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I'll include a plotted graph with our equation just so you can verify it is indeed the same.

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2 years ago

Suppose that a local TV station conducts a survey of a random sample of 120 registered voters in order to predict the winner of

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Answer:

a) The 99% CI for the true proportion of voters who prefer the Republican candidate is (0.3658, 0.6001). This means that we are 99% sure that the true population proportion of all voters who prefer the Republican candidate is (0.3658, 0.6001).

b) The upper bound of the confidence interval is above 0.5 = 50%, which meas that the candidate can be confidence of victory.

Step-by-step explanation:

Question a:

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

$\pi \pm z\sqrt{\frac{\pi(1-\pi)}{n}}$

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The upper limit of this interval is:

$\pi + z\sqrt{\frac{\pi(1-\pi)}{n}} = 0.4833 + 2.575\sqrt{\frac{0.4833*0.5167}{120}} = 0.6001$

The 99% CI for the true proportion of voters who prefer the Republican candidate is (0.3658, 0.6001). This means that we are 99% sure that the true population proportion of all voters who prefer the Republican candidate is (0.3658, 0.6001).

b. If a candidate needs a simple majority of the votes to win the election, can the Republican candidate be confident of victory? Justify your response with an appropriate statistical argument.

The upper bound of the confidence interval is above 0.5 = 50%, which meas that the candidate can be confidence of victory.

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2 years ago