Another college precalculas question, please and thank you!

What is 5 divided by 25

disa [49]

Answer:

0.2

Step-by-step explanation:

5 0

3 years ago

Read 2 more answers

Simplify: (7+2a)·3–20 =

Black_prince [1.1K]

<h2>Greetings!</h2>

Answer:

6a + 1

Step-by-step explanation:

First, you need to multiply everything in the brackets by 3L

(7 + 2a) x 3 =

7 * 3 = 21

2a * 3 = 6a

21 + 6a

Now you can subtract the 20 from this:

6a + 21 - 20

Simplified down:

6a + 1

<h2>Hope this helps!</h2>

6 0

3 years ago

you plan to go snowboarding this weekend in Pennsylvania. the resort charges $15.75 per hour in addition to a $25 deposit to ren

Ulleksa [173]

Answer:

A. Equation is $c=25+15.75x$

B. Cost is $88

Step-by-step explanation:

A)

Suppose you rent for x hours and each hour costs $15.75

<u><em>How much would you need to pay?</em></u>

$15.75x$

Moreover, there is a $25 dollar (fixed) deposit for renting, so that gets added to your payment. All in all, you have to pay $25+15.75x$

This is the equation of renting a snowboard for x hours.

Equation is $c=25+15.75x$

Where x is the number of hours you rent the snowboard, and
c is the total cost

B)

If you are renting from 8.30 to 12.30, you are basically renting for 4 hours.

To know how much it will cost, you simply plug in 4 into x (in the equation):

$c=25+15.75x\\c=25+15.75(4)\\c=88$

Cost is $88

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

The weights of four puppies are shown in pounds

storchak [24]

Answer:

9.125 9, 9.59

Step-by-step explanation:

3 0

3 years ago