Please answer for branliest

This question is incomplete, the complete question is;

Customers arrive at a movie theater at the advertised movie time only to find that they have to sit through several previews and preview ads before the movie starts. Many complain that the time devoted to previews is too long (The Wall Street Journal, October 12, 2012). A preliminary sample conducted by The Wall Street Journal showed that the standard deviation of the amount of time devoted to previews was 4 minutes. Use that as a planning value for the standard deviation in answering the following questions. Round your answer to next whole number,

a) If we want to estimate the population mean time for previews at movie theaters with a margin of error of 75 seconds, what sample size should be used? Assume 95% confidence.

b) If we want to estimate the population mean time for previews at movie theaters with a margin of error of 1 minute, what sample size should be used? Assume 95% confidence.

Answer:

a) the required Sample Size is 40

b) the required Sample Size is 62

Step-by-step explanation:

Given the data in the question;

standard deviation σ = 4 minutes

a)

margin of error E = 75 seconds = ( 75 / 60 )minutes = 1.25 minutes

And 95% confidence.

Now, Critical Value of z for 0.95 confidence interval;

∝ = 1 - 0.95 = 0.05

[tex]Z_{\alpha /2[/tex] = 1.96

so, sample size n will be;

n = [ [tex]Z_{\alpha /2[/tex] × σ/E ]²

we substitute;

n = [ 1.96 × (4/1.25) ]²

n =  [ 1.96 × 3.2 ]²

n = [ 6.272 ]²

n = 39.338

Since we referring to a number of sample, its approximately becomes 40

Therefore, the required Sample Size is 40

b)

margin of error E = 1 minutes

And 95% confidence.

Now, Critical Value of z for 0.95 confidence interval;

∝ = 1 - 0.95 = 0.05

[tex]Z_{\alpha /2[/tex] = 1.96

so, sample size n will be;

n = [ [tex]Z_{\alpha /2[/tex] × σ/E ]²

we substitute;

n = [ 1.96 × (4/1) ]²

n =  [ 1.96 × 4 ]²

n = [ 7.84 ]²

n = 61.466

Since we referring to a number of sample, its approximately becomes 62

Therefore, the required Sample Size is 62

Step-by-step explanation:

......................

Answer:50

Step-by-step explanation:

Answer:

C. 2

Step-by-step explanation:

Cancel log from both sides,

2t + 4 = 14 - 3t

5t = 10

t = 2

Answer:

6.05

Step-by-step explanation:

12 and a half percent of 48.4 = 6.05 because you can put .125 in your calculator and it is the same at 12.5% so you do .125 * 48.40 and you get 6.05

The terminal point of the unit circle (cos θ, sine θ) for 30° is                     ( √3/2 , 1/2 ).

"The terminal point is the ray that has been rotated around the origin to form an angle with the stationary ray which is the initial side of the angle. They are sine and cosine values of the most common acute-angle measures".

For the given question,

Angle = 30°

The terminal point on the unit circle has the cosine as x -coordinate and the sine as y - coordinate are mostly acute-angle measures.

Here, θ = 30°

The x-coordinate is cos 30° = [tex]\frac{\sqrt{3} }{2}[/tex]

The y-coordinate is sin 30° = [tex]\frac{1}{2}[/tex]

Hence we can conclude that the terminal point for 30° is ( √3/2 , 1/2).

Learn more about terminal points of circles here

https://brainly.com/question/23361272

#SPJ2

Answer:

Hihi <333

Step-by-step explanation:

The answer is C.

Whenever looking at questions from this site make sure to carefully read your question so you don't accidentally click the wrong answer

Answer:

C(0,6)

Step-by-step explanation:

1) find the length of the base of the triangle

AB = 7-3 = 4

2) find the the height of the triangle

A = (base x height)/2

A x 2 = base x height

height = (A x 2)/base

height = (12 x 2)/4 = 6

3) find the equation of the line that passes threw the points AB

the two points have the same y so the equation of the line is

y = 0

4) use the formula of the distance between a point and a line to find C

|ax+by+c|/√a^2 + b^2 = distance

x = 0  

y = 6

C (0,6)

Answer:

[tex]W = 13.29^\circ[/tex]

Step-by-step explanation:

Given

[tex]\sin(W) = 0.23[/tex]

Required

Find W

Take arc sin of both sides

[tex]W = \sin^{-1}(0.23)[/tex]

Using a calculator

[tex]W = 13.29^\circ[/tex]

Answer:

[tex] \frac{5}{24} [/tex]

Step-by-step explanation:

Given:

[tex] \frac{7}{8} - \frac{2}{3} [/tex]

Required:

Difference of the fractions in simplified form

Solution:

[tex] \frac{7}{8} - \frac{2}{3} [/tex]

The common denominator of both fractions is 24

Therefore:

[tex] \frac{3*7 - 8*2}{24} [/tex]

[tex] \frac{21 - 16}{24} [/tex]

[tex] \frac{5}{24} [/tex]

Answer:

a. 0.4364 = 43.64% probability that the total of their scores is above 260.

b. 0.0351 = 3.51% probability that Jeff's score is higher.

Step-by-step explanation:

Normal Probability Distribution:

Problems of normal distributions can be solved using the z-score formula.

In a set with mean [tex]\mu[/tex] and standard deviation [tex]\sigma[/tex], the z-score of a measure X is given by:

[tex]Z = \frac{X - \mu}{\sigma}[/tex]

The Z-score measures how many standard deviations the measure is from the mean. After finding the Z-score, we look at the z-score table and find the p-value associated with this z-score. This p-value is the probability that the value of the measure is smaller than X, that is, the percentile of X. Subtracting 1 by the p-value, we get the probability that the value of the measure is greater than X.

Sum/Subtraction between normal variables:

When two normal variables are added/subtracted, the mean is the sum/subtraction of the means, while the standard deviation is the square root of the sum of the variances.

a. the total of their scores is above 260.

Mean is the sum of the means, so:

[tex]\mu = 100 + 155 = 255[/tex]

Standard deviation is the square root of the sum of the variances. So

[tex]\sigma = \sqrt{21^2+22^2} = 30.4[/tex]

The probability is 1 subtracted by the p-value of Z when X = 260. So

[tex]Z = \frac{X - \mu}{\sigma}[/tex]

[tex]Z = \frac{260 - 255}{30.4}[/tex]

[tex]Z = 0.16[/tex]

[tex]Z = 0.16[/tex] has a p-value of 0.5636

1 - 0.5636 = 0.4364

0.4364 = 43.64% probability that the total of their scores is above 260.

b. Jeff's score is higher.

Jeff's mean is of 100, while Pam's is of 155. The probability of Jeff's score being higher is the probability that the subtraction is above 0. The mean is:

[tex]\mu = 100 - 155 = -55[/tex]

The probability is 1 subtracted by the p-value of Z when X = 0. So

[tex]Z = \frac{X - \mu}{\sigma}[/tex]

[tex]Z = \frac{0 - (-55)}{30.4}[/tex]

[tex]Z = 1.81[/tex]

[tex]Z = 1.81[/tex] has a p-value of 0.9649.

1 - 0.9649 = 0.0351

0.0351 = 3.51% probability that Jeff's score is higher.

Answer:

A = 533.8 square inches

Step-by-step explanation:

Use the surface area of a cylinder formula (A=2πrh+2πr^2)

Plug in 12 for h and 5 for r

Use 3.14 in replace for π

A = 2(3.14)(5)(12) + 2(3.14)(5)^2

A = 533.8 in^2

Step-by-step explanation:

55 square inches tall is the average cost of a house in the morning po everything is the same as

Answer:

It may be A. or C.

Step-by-step explanation:

A. 5 = 20 4 = 16  4 = 16 20 + 16 = 36 + 16 = 52

B.  3 = 12 3 = 12 7 = 27 + 12 = 39 + 12 = 51

i uhhh don't know this is confusing

im very sorry if im incorrect

Answer:

not c

sorry its not exact

9514 1404 393

Explanation:

Shrinkage is the loss of inventory from causes other than normal use or sales. It is the difference between the inventory on the books and the amount of inventory actually available for use. Typical causes of shrinkage are theft, damage, fraud, counting error, administrative error.

Answer:

Chaeyoung!!!!

Step-by-step explanation:

I love Twice!!!

Answer:

Circumference of given circle = 154 cm² (Approx.)

Step-by-step explanation:

In given diagram:

Diameter of given radius = 49 cm

Value of π = 3.14

Find:

Circumference of given circle

Computation:

Radius of given circle = Diameter of given radius / 2

Radius of given circle = 49 / 2

Circumference of given circle = 2πr

Circumference of given circle = 2(3.14)(49/2)

Circumference of given circle = (6.28)(49/2)

Circumference of given circle = 153.86

Circumference of given circle = 154 cm² (Approx.)

Answer:    

.

Step-by-step explanation:

X goes left and right. Y goes up and down. Hope this help:)

Answer: 43/75 chance

Step-by-step explanation:

total number of coins:

15 + 28 + 12 + 20 = 75

total number of coins that arent quarters or dimes:

15 + 28 = 43

so the probability would be 43/75, which is not simplifiable

Answer:

Since Tina wants to buy grass seed to cover her whole lawn, except for the pool, and the pool is 7/12 m by 3/14 m, to find the area the grass seed needs to cover the following calculation must be performed:

It is impossible to determine the area that the grass seed needs to cover, because we do not have the data of the total size of the lawn. Now, you can determine the size of the surface that should not be covered, which is the one that the pool occupies, namely:

7/12 x 3/14 = X

0.583333 x 0.2142 = X

0.1249 = X

Therefore, the grass seed should not cover about 0.1249 square meters.

Answer:

5/2 and -5/2

sry i late

Answer:

18

Step-by-step explanation:

Answer: 6

Step-by-step explanation: Division use a calculator 12/2

Answer:

6

Step-by-step explanation:

From question:

Dan has put his coins into 2 stacks

2 stacks in total

Each stack has the same number of coins

Number of coins in stack 1 = number of coins in stack 2

x = x

There are 12 coins total

Total number of coins in 2 stacks = 12

2x = 12

x = 6

There are six coins in one stack.

Answer:

my answer would be c. y=lX+7l

Answer:

120

Step-by-step explanation:

2x plus 3x/4 + x =18

add like terms

well first i mutliplied both sides by 4 to get it out of the way

and then i added the x's

so now its 2x+3x+x=180

now its 6x=`180

180/6=120

x=120

Answer:

96 divided by 8 = 12

Step-by-step explanation:

Answer:

13

Step-by-step explanation:

9514 1404 393

Answer:

  24

Step-by-step explanation:

Assuming that making the cut does not change the total length of the board, each foot can be divided into two pieces that are 1/2 foot. The number of pieces will be ...

  (12 ft)/(1/2 ft/piece) = (12×2) pieces = 24 pieces

Ross can make 24 pieces that are 1/2 ft long from her board.