Does some one want to help me out with a couple questions I don’t get.

Bob Nale is the owner of Nale’s Quick Fill. Bob would like to estimate the mean number of gallons of gasoline sold to his custom

ira [324]

Answer:

a) The best estimator for the population mean is given by the sample mean $\hat \mu = \bar X = 5.70$

b) The 99% confidence interval would be given by (4.969;6.431)

c) We are 99% confident that the true mean for th number of gallons of gasoline sold to his customers is between 4.969 and 6.431.

Step-by-step explanation:

1) Previous concepts

A confidence interval is "a range of values that’s likely to include a population value with a certain degree of confidence. It is often expressed a % whereby a population means lies between an upper and lower interval".

The margin of error is the range of values below and above the sample statistic in a confidence interval.

Normal distribution, is a "probability distribution that is symmetric about the mean, showing that data near the mean are more frequent in occurrence than data far from the mean".

$\bar X$ represent the sample mean for the sample

$\mu$ population mean (variable of interest)

$\sigma=1.9$ represent the population standard deviation

n=45 represent the sample size

2) Part a

The best estimator for the population mean is given by the sample mean $\hat \mu = \bar X = 5.70$

3) Part b. Develop a 99 percent confidence interval for the population mean.

The confidence interval for the mean is given by the following formula:

$\bar X \pm z_{\alpha/2}\frac{\sigma}{\sqrt{n}}$ (1)

Since the Confidence is 0.95 or 95%, the value of $\alpha=0.01$ and $\alpha/2 =0.005$ , and we can use excel, a calculator or a table to find the critical value. The excel command would be: "=-NORM.INV(0.005,0,1)".And we see that $z_{\alpha/2}=2.58$

Now we have everything in order to replace into formula (1):

$5.7-2.58\frac{1.9}{\sqrt{45}}=4.969$

$5.7+2.58\frac{1.9}{\sqrt{45}}=6.431$

So on this case the 99% confidence interval would be given by (4.969;6.431)

4) Part c. Interpret the meaning of part (b).

On this case we can say this: We are 99% confident that the true mean for th number of gallons of gasoline sold to his customers is between 4.969 and 6.431.

4 0

4 years ago

Another question! A piece of fabric costs $5.29 a yard, which is an estimate cost of 16.3

lbvjy [14]

Answer:

B.)$80

5.29 times 16.3 is 86.227 but it is not close to 21 not 165 and not a 800 so the answer would be 80

6 0

3 years ago

Read 2 more answers

Order from least to greatest 3.2 ,3.14, 19/7, sqrt (14)

Oksanka [162]

Answer: 19/7 ,3.14, 3.2

Step-by-step explanation: Hope this helps Have a brilliant day of learning!

7 0

3 years ago

Data from the Centers for Medicare and Medicaid Services indicates that the annual per capita out-of-pocket expenses for health

Talja [164]

Answer:

During the year 2021.

Step-by-step explanation:

As we have a function that defines the annual per capita out-of-pocket expenses for health care, we can work with it.

Knowing that, we clear x (this is the number of years past the year 2000, so it will contain our desired information).

$y=39.6x+543\Leftrightarrow x=\frac{y-543}{39.6}$

Now, as we want to know when are the per capita out-of-pocket expenses for health care predicted to be $1400, and this total is our variable y, then

$x=\frac{1400-543}{39.6}\approx 21.6$

Finally, we know that x is the number of years past the year 2000, so the answer is that during the year 2021, the per capita out-of-pocket expenses for health care are predicted to be $1400.

3 0

3 years ago

1. Find the slope of the line that goes through the points (2, 5) and (6, 7)

ella [17]

Answer:

$\displaystyle m = \frac{1}{2}$