The amount people who pay for electric service varies quite a bit, but the mean monthly fee is $168 and the standard deviation i
s $34. The distribution is not Normal. Many people pay about $90 in rural areas of the country and about $150 in urban areas of the country, but some pay much more. A sample survey is designed to ask a simple random sample of 1,200 people how much they pay for electric services. Let xbar be the mean amount paid. Part A: What are the mean and standard deviation of the sample distribution of xbar? Show your work and justify your reasoning. (4 points) Part B: What is the shape of the sampling distribution of xbar? Justify your answer. (2 points) Part C: What is the probability that the average electric service paid by the sample of electric service customers will exceed $170? Show your work. (4 points)
1 answer:
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Don't let fractions fool you.
of a tank in 
an hour is equal to:
1/12 of a tank in 20 minutes.
Thus we know in an hour, an oil company can fill 3/12 of a tank (60 minutes in an hour).
3 x 4 = 12, and 12/12 = 1(a whole tank), so we multiply 1 (hour) by 4.
Our answer is that it takes 4 hours to fill a tank.
1/12 of a tank in 20 minutes.
Thus we know in an hour, an oil company can fill 3/12 of a tank (60 minutes in an hour).
3 x 4 = 12, and 12/12 = 1(a whole tank), so we multiply 1 (hour) by 4.
Our answer is that it takes 4 hours to fill a tank.
Answer:
The longer length is either 99, 33 or 11 inches
Step-by-step explanation:
Given
Required
The length of the longer side
Area of a rectangle is:
List out all possible products that give 99 [Assume the dimension are whole numbers]
List out the longer factors
<em>Hence, the longer length is either 99, 33 or 11 inches</em>