Help !! what is the expected value for the binomial distribution below ?

ddd [48]

Y + 4x < 8
y < -4x + 8
2 points that satisfy this are (0,8) and (2,0)....and those happen to be ur x and y intercepts (where the line crosses the x and y axis)

graph...so go ahead and plot ur x and y intercepts (0,8) and (2,0).....ur slope is - 4.....so start at ur y int (0,8) and go down 4 spaces, and to the right 1...plot that point, then go down 4 spaces and to the right 1, then plot that point...keep doing this and u will have ur line...u should have crossed the x axis at (0,2)......ur line will be a dashed line since the problem has no equal sign.... the shading will go below the line because it is less then.

y - 3 > = 1/2x
y > = 1/2x + 3
2 points that satisfy this are : (0,3) and (-6,0)...ur x and y intercepts

graph : plot ur intercepts (0,3) and (-6,0)....u have a slope of 1/2...so start at ur x intercept (-6,0) and go up 1 space, and to the right 2 spaces, plot that point...then go up 1 and to the right 2, plot that point...keep doing this and u will cross the y axis at (0,3)....this line will be a solid line....the shading will go above the line.

8 0

3 years ago

In a random sample of 80 teenagers, the average number of texts handled in a day is 50. The 96% confidence interval for the mean

Nastasia [14]

Answer:

a) $\bar X =\frac{46+54}{2}=50$

And the margin of error is given by:

$ME= \frac{54-46}{2}= 4$

The confidence level is 0.96 and the significance level is $\alpha=1-0.96=0.04$ and the value of $\alpha/2 =0.02$ and the margin of error is given by:

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

We can calculate the critical value and we got:

$z_{\alpha/2} = 2.05$

And if we solve for the deviation like this:

$\sigma = ME * \frac{\sqrt{n}}{z_{\alpha/2}}$

And replacing we got:

$\sigma =4 *\frac{\sqrt{80}}{2.05} =17.45$

b) $ME=z_{\alpha/2}\frac{\sigma}{\sqrt{n}}=2.05 *\frac{17.45}{\sqrt{160}}=2.828$

And as we can see that the margin of error would be lower than the original value of 4, the margin of error would be reduced by a factor $\sqrt{2}$

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

$\mu$ population mean (variable of interest)

$\sigma$ represent the population standard deviation

n=80 represent the sample size

Solution to the problem

Part a

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

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

For this case we can calculate the mean like this:

$\bar X =\frac{46+54}{2}=50$

And the margin of error is given by:

$ME= \frac{54-46}{2}= 4$

The confidence level is 0.96 and the significance level is $\alpha=1-0.96=0.04$ and the value of $\alpha/2 =0.02$ and the margin of error is given by:

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

We can calculate the critical value and we got:

$z_{\alpha/2} = 2.05$

And if we solve for the deviation like this:

$\sigma = ME * \frac{\sqrt{n}}{z_{\alpha/2}}$

And replacing we got:

$\sigma =4 *\frac{\sqrt{80}}{2.05} =17.45$

Part b

For this case is the sample size is doubled the margin of error would be:

$ME=z_{\alpha/2}\frac{\sigma}{\sqrt{n}}=2.05 *\frac{17.45}{\sqrt{160}}=2.828$

And as we can see that the margin of error would be lower than the original value of 4, the margin of error would be reduced by a factor $\sqrt{2}$

5 0

3 years ago

Let A = Aaron's age today and M = Maria's age today.

kondor19780726 [428]

Aaron is 4 years and Maria is 14 years old.

A = Aaron's age today

M = Maria's age today.

a. The equation based on the statement given will be:

M = A + 10

b. Maria's age based on the statement in 6 years will be:

= (A + 10) + 6

= A + 16

c. Based on the information above, the equation to solve their ages will be:

A + 16 = 2(A + 6)

A + 16 = 2A + 12

Collect like terms

2A - A = 16 - 12

A = 4

Therefore, Aaron is 4 and Maria is 14 years.

Read related link on:

brainly.com/question/22866879

3 0

3 years ago

Solve -5x2 - 20x + 35 = 30 by completing the square.

Semenov [28]

Answer:

x=−2−√5 or x=−2+√5

Step-by-step explanation:

-5x2 - 20x + 35 = 30

Answer = x=−2−√5 or x=−2+√5

5 0

3 years ago

Once again... we almost finish, solve for x

algol13

Answer:

x = 34

Step-by-step explanation:

Angles are supplementary:

x + 7 + 4x + 3 = 180

5x + 10 = 180

5x = 170

x = 34

3 0

3 years ago