Answer:
Step-by-step explanation:
Given that n =30, x bar = 375 and sigma = 81
Normal distribution is assumed and population std dev is known
Hence z critical values can be used.
For 95% Z critical=1.96
Margin of error = 
Confidence interval = 375±29
=(346,404)
B) 99% confidence
Margin of error = 2.59*Std error =38
Confidence interval = 375±38
=(337, 413)
C) For 90%
Margin of error = 20
Std error = 20/1.645 = 12.158
Sample size

Atleast 44 people should be sample size.
Answer: (6,7)
Step-by-step explanation:
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Explanation:</h2><h2>
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The diagram for this problem is shown below. Point E is the intersection of the two diagonals and we know that:

Every internal angle of any rectangle measures 90 degrees, so:

So:

So the measure of angle BEC can be found as follows:
We know that triangle ΔCEB is an isosceles triangle because the diagonals of any rectangle measure the same. So

The sum of internal angles of any triangle add up to 180 degrees, so:

Answer:
That would mean for every 30 campers there are 2 counselors and 45:3,60:4 and so on
Step-by-step explanation: