my lil sis needs help asap

Answer:

C is my answer

Step-by-step explanation:

Solution :

Let

Waiting time for accessing one record = W

Read time for moving the information = R

Total time for accessing to get one block of information = X

So, the random variable X is defined as :

X = W + R

  = W + 7

a). Calculating E(X)

E(X) = E(W+7)

      = E(W) + 7

      [tex]$=\int_{0}^{28}\frac{1}{28-0}w dw +7$[/tex]

       [tex]$=\frac{1}{28}\int_{0}^{28}w dw +7$[/tex]

       [tex]$=\frac{1}{28}\left[\frac{w^2}{2}\right]_0^{28}+7$[/tex]

      [tex]$=\frac{1}{56}\left[28^2\right]+7$[/tex]

      [tex]$=\frac{28}{2}+7$[/tex]

     = 14 + 7

     = 21

b). Calculating Var(X)

V(X) = V(W+7)

      = V(W)+0

      = V(W)

     = [tex]$E(W^2)-[E(W)]^2$[/tex]

     [tex]$=\int_0^{28}\frac{1}{28}w^2 dw-[14]^2$[/tex]

    [tex]$=\frac{1}{28}\left[\frac{w^3}{3}\right]_0^{28}-196$[/tex]

   [tex]$=\frac{1}{28\times 3}\times 28^3-196$[/tex]

  [tex]$=\frac{28\times 28}{3}-196$[/tex]

 = 65.33

c). Considering A is the random variable that can be defined as follows:

A = 6(W+7)

   =6W + 42

So calculating E(A)

E(A) = E(6W + 42)

      = E(6W) +42

      = 6E(W) + 42

     = 6(14) + 42

     = 84 + 42

     = 126

Answer:  17.2 for each tank

Answer:

A. 4.71cm²

Step-by-step explanation:

Area of a sector = π(radius²)(angle/360)

=π(3²)(60/360)

=(9)(1/6)π=4.71238898038

Answer:

Step-by-step explanation:

let the base=12x

and height=5x

(12x)²+(5x)²=37.7²

144x²+25x²=37.7²

169x²=37.7²

(13x)²=37.7²

13x=37.7

x=37.7/13=2.9

base=12×2.9=34.8 ft

height=5×2.9=14.5 ft

Answer:

44 dollars without tax so the earrings were 11 dollars off

Answer:

The slope should be 34.00.

Step-by-step explanation:

Answer:

1500mm

Step-by-step explanation:

Multiply the length by 1000

therefore, 1.5×1000

Answer:

[tex]\frac{\pi}{3}[/tex] radians

Step-by-step explanation:

Number of hours on a clock = 12

Since, measure of a circle at the center = 360°

Measure of central angle formed by the arc between each number (representing hours) = [tex]\frac{360}{12}[/tex]

                                  = 30°

Central angle formed by the arc intercepted by the hands of the clock at 8:00 = 4 × 30°

        = 120°

Therefore, angle measure in radians = [tex]\frac{\pi }{360}\times (120^0)[/tex]

                                                              = [tex]\frac{\pi }{3}[/tex]

Angle formed by the hands of the clock at 8:00 = [tex]\frac{\pi}{3}[/tex] radians

Answer:

The probability that both number cubes have the number 4 facing up is 1/36.

Step-by-step explanation:

For a cube, we have the number:

1,2,3,4,5 and 6

The number 4 only occurs once in the six.

So, the probability of having the number 4 in a single roll is 1/6.

Now, for two rolls, we have two probabilities which we will have to multiply.

Thus, we have the probability as:

[tex] \frac{1}{6} \times \frac{1}{6} = \frac{1}{36} [/tex]

Answer:

22

Step-by-step explanation:

9514 1404 393

Answer:

  widen

Step-by-step explanation:

The vertical scale factor is 3/4, so the vertical extent is shortened at a given x-value distance from the axis of symmetry. That will give the appearance of making the parabola (slightly) wider.

Answer:

Step-by-step explanation:

Answer:

29°

Step-by-step explanation:

151° + a=180°

We know the sum of angles in a straight line is 180°

a= 180°-151°

The sign changed as it changed sides

a= 29°

Answer:

The median is 9

Step-by-step explanation:

Answer:

Hey love! Answer: 9

Step-by-step explanation:

these are the numbers 5 6 7 8 (9) 10 11 12 13

the median is simply just the one in the middle so this one is 9 because it has 4 numbers in front and 4 numbers after

Hope this helps!

Answer:

Surface area = 24in

Step-by-step explanation:

I think its 6in x 4in

so like since the green cylinder is 6in i think you multiply it with the purple (sorry if I’m wrong)

Answer:

DONT CLICK THE LINK!!!! IT IS A BOT. THEY WILL. HACK.

Step-by-step explanation:

Given, we know that she has 14 bricks.

We also know that the patio is 4 yards long and 3 yards wide. If we multiply those two numbers together we get 12.

So, if we do the math 14-12=2 bricks left over.

Therefore, she will have enough bricks to build the patio.

Answer: 7.5 miles

Step-by-step explanation:

think of it as a triangle; the bold line is the hypotenuse, or x.

 8   |\   x

      |_\              it's not a good triangle but you get the point

       6

and then get out pythagorean theorem: a^2+b^2=c^2

put the numbers in: 8^2 + 6^2 = x^2

do some math:

64+36=x^2

100=x^2 (and then find square root)

10=x

BUT, it said each unit was 3/4 of a mile, so we must multiply 10 by 3/4 to get the actual distance, which is 7.5

Answer:

48/20=2.4

12/2.4=5

Step-by-step explanation:

Kai can buy 5 bunches of grapes if she has $12.

Answer:

It's 29.

Step-by-step explanation:

48/20=2.4

12x2.4=28.8

Round up to 29.

Answer:

Where is the question

Step-by-step explanation:

Answer:

The pvalue of the test is 0.177 > 0.02, which means that at α=0.02, you cannot reject the company's claim.

Step-by-step explanation:

A company that makes cola drinks states that the mean caffeine content per​ 12-ounce bottle of cola is 35 milligrams. You want to test this claim.

At the null hypothesis, you test that the mean caffeine content is of 35 milligrams, that is:

[tex]H_o: \mu = 35[/tex]

And at the alternate hypothesis, you test if the content is different from 35, so:

[tex]H_a: \mu \neq 35[/tex]

The test statistic is:

[tex]z = \frac{X - \mu}{\frac{\sigma}{\sqrt{n}}}[/tex]

In which X is the sample mean, [tex]\mu[/tex] is the value tested at the null hypothesis, [tex]\sigma[/tex] is the standard deviation and n is the size of the sample.

35 is tested at the null hypothesis:

This means that [tex]\mu = 35[/tex]

During your​ tests, you find that a random sample of thirty​ 12-ounce bottles of cola has a mean caffeine content of 36.8 milligrams. Assume the population is normally distributed and the population standard deviation is 7.3 milligrams.

This means that [tex]n = 30, X = 36.8, \sigma = 7.3[/tex]

Value of the test statistic:

[tex]z = \frac{X - \mu}{\frac{\sigma}{\sqrt{n}}}[/tex]

[tex]z = \frac{36.8 - 35}{\frac{7.3}{\sqrt{30}}}[/tex]

[tex]z = 1.35[/tex]

Pvalue of the test and decision:

The pvalue of the test is the probability of the mean caffeine content differing from the mean by at least 36.8 - 35 = 1.8, which is P(|z| > 1.35), which is 2 multiplied by the pvalue of z = -1.35.

Looking at the z = -1.35 has a pvalue of 0.0885

2*0.0885 = 0.177

The pvalue of the test is 0.177 > 0.02, which means that at α=0.02, you cannot reject the company's claim.

Answer:

(2,1)

Step-by-step explanation:

f(x) = - x^2 + 4x - 3

Factor out the negative

f(x) = - (x^2 - 4x + 3)

Factor

f(x) = -(x-3) (x-1)

The zeros are at

0 = -(x-3) (x-1)

 x-3 =0   x-1 =0

x=3   x=1

We know the vertex is 1/2 way between the zeros

(3+1)/2 = 4/2 =2

The x coordinate of the vertex is 2

Substitute x=2 into the equation

f(2) = -(2^2-4(2) +3)

     = -(4-8+3)

    = -(-1)

    = 1

The vertex is (2,1)

[tex]\huge{\textbf{\textsf{{\color{pink}{An}}{\red{sw}}{\orange{er}} {\color{yellow}{:}}}}}[/tex]

D. 400 sq units

The surface area of the right prism given below is 432 square units.

The area of a three dimensional object on it's outer surface is called the surface area of the object.

Given a right prism.

The right prism consists of three rectangular faces and two triangular faces.

Area of a triangular face = 1/2 × 8 × 6 = 24

Area of two triangular faces = 2 × 24 = 48 square units

Area of rectangular faces = (10 × 16) + (8 × 16) + (6 × 16)

                                          = 384 square units

Total area of the prism = 48 square units + 384 square units

                                      = 432 square units

Hence the total area of the prism is 432 square units.

Learn more about Surface Area here :

https://brainly.com/question/29298005

#SPJ7

Answer:

y = 2/5x +2

Step-by-step explanation:

y - 4 = 2/5(x -5)

y-4 = 2/5x -2

y = 2/5x +2

Answer:

0.23825

Step-by-step explanation:

Given :

p = 0.592 ; number of trials, n = 8

x = 4 ; q = 1 - p = 1 - 0.592 = 0.408

Using the binomial probability relation :

P(x = x) = nCx * p^x * q^(n-x)

P(x = 4) = 8C4 * 0.592^4 * 0.408^4

P(x = 4) = 70 * 0.592^4 * 0.408^4

P(x = 4) = 0.23825

Answer:

mk?

Step-by-step explanation:

Answer:

1.the square pan is larger by 12 inches

40 cm^2

Step-by-step explanation:

The difference in size can be determined by calculating the difference between the perimeter of the square pan and the circumference of a circle

perimeter of a square = 4 x length

14 x 4 = 56 inches

Circumference of a circle = πD = (22/7) x 14 = 44 inches

Difference in size = 56 - 44 = 12 inches

Area of a rectangle = length x width

10 x 4 - 40 cm^2

Answer:

[tex]1 \to 22 \to 0.176[/tex]

[tex]2 \to 13 \to 0.104[/tex]

[tex]3 \to 18 \to 0.144[/tex]

[tex]4 \to 29 \to 0.232[/tex]

[tex]5 \to 37 \to 0.296[/tex]

[tex]6 \to 6 \to 0.048[/tex]

Step-by-step explanation:

Given

[tex]n = 125[/tex]

See attachment for proper table

Required

Complete the table

Experimental probability is calculated as:

[tex]Pr = \frac{Frequency}{n}[/tex]

We use the above formula when the frequency is known.

For result of roll 2, 4 and 6

The frequencies are 13, 29 and 6, respectively

So, we have:

[tex]Pr(2) = \frac{13}{125} = 0.104[/tex]

[tex]Pr(4) = \frac{29}{125} = 0.232[/tex]

[tex]Pr(6) = \frac{6}{125} = 0.048[/tex]

When the frequency is to be calculated, we use:

[tex]Pr = \frac{Frequency}{n}[/tex]

[tex]Frequency = n * Pr[/tex]

For result of roll 3 and 5

The probabilities are 0.144 and 0.296, respectively

So, we have:

[tex]Frequency(3) = 125 * 0.144 = 18[/tex]

[tex]Frequency(5) = 125 * 0.296 = 37[/tex]

For roll of 1 where the frequency and the probability are not known, we use:

[tex]Total \ Frequency = 125[/tex]

So:

Frequency(1) added to others must equal 125

This gives:

[tex]Frequency(1) + 13 + 18 + 29 + 37 + 6 = 125[/tex]

[tex]Frequency(1) + 103 = 125[/tex]

Collect like terms

[tex]Frequency(1) =- 103 + 125[/tex]

[tex]Frequency(1) =22[/tex]

The probability is then calculated as:

[tex]Pr(1) = \frac{22}{125}[/tex]

[tex]Pr(1) = 0.176[/tex]

So, the complete table is:

[tex]1 \to 22 \to 0.176[/tex]

[tex]2 \to 13 \to 0.104[/tex]

[tex]3 \to 18 \to 0.144[/tex]

[tex]4 \to 29 \to 0.232[/tex]

[tex]5 \to 37 \to 0.296[/tex]

[tex]6 \to 6 \to 0.048[/tex]

Answer:

25 feet

Step-by-step explanation: