Given the function f(x) = 9x2 + 27x + 2, find f(2).

oee [108]

If solving for x you will first need to combine like terms. Then after getting the amount of numbers and amount of x numbers you will divide the x number from both. After doing that you would get X=-10

7 0

2 years ago

What is the probability of selecting a seventh-grader from a school that has 250 sixth-graders, 225 seventh-graders, and 275 eig

Nina [5.8K]

Answer:

3/10 or 0.3 or 30%

Step-by-step explanation:

Its 225/750 total students

We simplify this by dividing by 5

45/150

Divide by 5 again

9/30

Divide by 3

3/10

3 0

3 years ago

A union of restaurant and foodservice workers would like to estimate the mean hourly wage, μ, of foodservice workers in the U.S.

pav-90 [236]

Answer:

$n=(\frac{1.960(2.25)}{0.35})^2 =158.76 \approx 159$

So the answer for this case would be n=159 rounded up to the nearest integer

Step-by-step explanation:

Assuming this complete question: A union of restaurant and foodservice workers would like to estimate the mean hourly wage, , of foodservice workers in the U.S. The union will choose a random sample of wages and then estimate using the mean of the sample. What is the minimum sample size needed in order for the union to be 95% confident that its estimate is within $0.35 of ? Suppose that the standard deviation of wages of foodservice workers in the U.S. is about $2.15 .

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)

$\sigma=2.25$ represent the population standard deviation

n represent the sample size

Solution to the problem

Since the Confidence is 0.95 or 95%, the value of $\alpha=0.05$ The margin of error is given by this formula:

$ME=z_{\alpha/2}\frac{s}{\sqrt{n}}$ (a)

And on this case we have that ME =0.35 and we are interested in order to find the value of n, if we solve n from equation (a) we got:

$n=(\frac{z_{\alpha/2} \sigma}{ME})^2$ (b)

The critical value for 95% of confidence interval now can be founded using the normal distribution. And in excel we can use this formla to find it:"=-NORM.INV(0.025;0;1)", and we got $z_{\alpha/2}=1.960$ , replacing into formula (b) we got:

$n=(\frac{1.960(2.25)}{0.35})^2 =158.76 \approx 159$

So the answer for this case would be n=159 rounded up to the nearest integer

3 0

2 years ago

The table below gives data from a linear function. find a formula for the function.

baherus [9]

Given the following table that gives data from a linear function:

$\begin {tabular}
{|c|c|c|c|}
Temperature, $y = f(x)$ (^\circ C)&0&5&20 \\ [1ex]
Temperature, $x$ (^\circ F)&32&41&68 \\ 
\end {tabular}$

The formular for the function can be obtained by choosing two points from the table and using the formular for the equation of a straight line.

Recall that the equation of a straight line is given by
$\frac{y-y_1}{x-x_1} = \frac{y_2-y_1}{x_2-x_1}$

Using the points (32, 0) and (41, 5), we have:
$\frac{y-0}{x-32} = \frac{5-0}{41-32}= \frac{5}{9} \\ \\ \Rightarrow y=\frac{5}{9}(x-32)$

4 0

2 years ago

if you have 35 and you're friend gives you 35 more then someone takes 15 then you give 10 away and you ate 19 then you're friend

emmainna [20.7K]

49.

35+35-15-10-19+23 is 49.

8 0

2 years ago

Given the function f(x) = 9x2 + 27x + 2, find f(2).​

Given the function f(x) = 9x2 + 27x + 2, find f(2).