Randall bought 2 game controllers at Electronics Plus for $36. What is the unit rate for game controller at Electronics Plus?

Evaluate the function f(x) = –2x2 – 3x + 5 for the input value –3.

Elza [17]

Answer:

10

Step-by-step explanation:

-2*2-3x+5=f(x)

-2*2-3(-3)+5=f(x)

-4+9+5=f(x)

5+5=f(x)

10=f(x)

3 0

3 years ago

Tìm giá trị lớn nhất và giá trị nhỏ nhất của hàm số <br> y=40<img src="https://tex.z-dn.net/?f=%5Csqrt%7B%28x-1%29x%5E%7B3%20%7D

Doss [256]

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3 0

3 years ago

Express $7.45 for 2.5 pounds of round steak as a unit rate.

Digiron [165]

unit rate: $7.45/2.5 lbs of steak

--------------------------------

reduced:

7.45 dollars /2.5 pounds

GCF=0.5

7.45/0.5=14.9$

2.5/0.5=5

unit rate:

$14.9/5 pounds

6 0

3 years ago

The current process has a mean of 2.50 and a std deviation of 0.05. A new process has been suggested by research. What sample si

Novay_Z [31]

Answer:

$ME=z_{\alpha/2}\frac{\sigma}{\sqrt{n}}$ (1)

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

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 $z_{\alpha/2}=1.96$ , replacing into formula (2) we got:

$n=(\frac{1.96(0.05)}{0.02})^2 =24.01$

So the answer for this case would be n=25 rounded up to the nearest integer

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".

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

$\mu$ population mean (variable of interest)

$\sigma=0.05$ represent the population standard deviation

n represent the sample size (variable of interest)

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

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

The margin of error is given by this formula:

$ME=z_{\alpha/2}\frac{\sigma}{\sqrt{n}}$ (1)

And on this case we have that ME =0.02 and we are interested in order to find the value of n, if we solve n from equation (1) we got:

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

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 $z_{\alpha/2}=1.96$ , replacing into formula (2) we got:

$n=(\frac{1.96(0.05)}{0.02})^2 =24.01$

So the answer for this case would be n=25 rounded up to the nearest integer

7 0

3 years ago

A cylindrical tank has a diameter of 2.5 feet and a height of 4.8 feet. what is the lateral surface area of the tank to the near

blsea [12.9K]

Answer:

This is approximately $37.7 ft^{2}$ to the nearest hundredth

Step-by-step explanation:

First of all, we will need to understand that to find the lateral surface area of the cylinder, we simply need to multiply the circumference of the circular base by the height of the cylinder.

In this case, the circumference of the circular base can be obtained by the formula

$2 \pi r$

Hence we will have the circumference as $2 \times \pi \times \frac{2.5}{2}=7.85 feet$

Tp get the Lateral area, we will simply have to multiply this value (7.85 feet )

by the height (4.8 feet)

7.85 X 4.8 = $37.68 feet ^{2}$

This is approximately $37.7 ft^{2}$ to the nearest hundredth

8 0

3 years ago