Need answer ASAP. Worth 25 points

In this figure please see questions

labwork [276]

Answer:

15,700

Step-by-step explanation:

The formula is 3.14(r^2)h

Hope this helped :)

3 0

3 years ago

Please can someone do this for me? thanks alot x

Nimfa-mama [501]

Answer:

Learning Objective: Use the mean and range to compare the spread and averages.

a) Sarah Mean = 70.9, Katie Mean = 78.9

b) Sarah Range = 15, Katie Range = 25

c) Sentences

- The mean shows, on average, Sarah was 8 seconds quicker than Katie.

- The range shows that Sarah was more consistent with her times. Katie had a larger spread of times which shows she was less consistent.

Step-by-step explanation:

Given:

Sarah's Data Set:

79, 70, 68, 75, 69, 64, 69, 75, 64, 76

Katie's Data Set:

79, 79, 76, 81, 89, 76, 64, 85, 82, 78

To Find:

The mean and range of both data sets separately.

Work:

The mean of a data set is commonly known as the average. You find the mean by taking the sum of all the data values and dividing that sum by the total number of data values. The formula for the mean of a population is $\mu = \frac{{\sum}x}{N}$ .

The formula for the mean of a sample is $\bar{x} = \frac{{\sum}x}{n}$ .

Both of these formulas use the same mathematical process: find the sum of the data values and divide by the total. For the data values given above, the solution is: $\frac{709}{10} = 70.9$

Therefore, the mean of Sarah's data set is 70.9.

For Katie's Data Set, $\frac{789}{10} = 78.9$ .

Therefore, the mean of Katie's data set is 78.9.

To fill in the summary, we have to use the data we just calculated.

That summary can be found in the answer section.

4 0

2 years ago

Read 2 more answers

POSSIBLE POINTS: 10

ASHA 777 [7]

Step-by-step explanation:

I'm going to assume 50.25 was a typo error and it is $0.25 for each extra minute.

For a 10 minute phone call, the first 5 minutes cost $3 and the other 5 minutes cost $0.25 * 5 = $1.25. Altogether it costs $4.25.

For a 15.5 minute phone call, the first 5 minutes cost $3 and the other 10.5 minutes cost $0.25 * 11 = $2.75. Altogether it costs $5.75.

8 0

3 years ago

Read 2 more answers

Consider the following random sample from a normal population: 14, 10, 13, 16, 12, 18, 15, and 11. What is the 95% confidence in

seraphim [82]

Answer:

$13.625-2.365\frac{2.669}{\sqrt{8}}=11.393$

$13.625+2.365\frac{2.669}{\sqrt{8}}=15.857$

So on this case the 95% confidence interval would be given by (11.393;15.857)

Step-by-step explanation:

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".

Data: 14, 10, 13, 16, 12, 18, 15, 11

We can calculate the sample mean and deviation with the following formulas:

$\bar X = \frac{\sum_{i=1}^n X_i}{n}$

$s = \sqrt{\frac{\sum_{i=1}^n (X_i -\bar X)^2}{n-1}}$

$\bar X=13.625$ represent the sample mean

$\mu$ population mean (variable of interest)

s=2.669 represent the sample standard deviation

n=8 represent the sample size

Calculate the confidence interval

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

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

In order to calculate the critical value $t_{\alpha/2}$ we need to find first the degrees of freedom, given by:

$df=n-1=8-1=7$

Since the confidence is 0.95 or 95%, the value of $\alpha=0.05$ and $\alpha/2 =0.025$ , and we can use excel, a calculator or a table to find the critical value. The excel command would be: "=-T.INV(0.025,7)".And we see that $t_{\alpha/2}=2.365$