You are going to estimate how long a person holds down a button on their calculator by randomly selecting people and asking them to do something on your calculator (which has a special timer to record how long the enter button is pressed). You practiced on the people at work and found a standard deviation of about 0.37 seconds. You want to get a 94% confidence interval that is only 0.06 in width. How many people do you need to have in your study

Answers

Answer 1

Answer:

You need to have 538 people in your study.

Step-by-step explanation:

We have that to find our [tex]\alpha[/tex] level, that is the subtraction of 1 by the confidence interval divided by 2. So:

[tex]\alpha = \frac{1 - 0.94}{2} = 0.03[/tex]

Now, we have to find z in the Ztable as such z has a pvalue of [tex]1 - \alpha[/tex].

That is z with a pvalue of [tex]1 - 0.03 = 0.97[/tex], so Z = 1.88.

Now, find the margin of error M as such

[tex]M = z\frac{\sigma}{\sqrt{n}}[/tex]

In which [tex]\sigma[/tex] is the standard deviation of the population and n is the size of the sample.

You practiced on the people at work and found a standard deviation of about 0.37 seconds.

This means that [tex]\sigma = 0.37[/tex]

You want to get a 94% confidence interval that is only 0.06 in width.

This means that [tex]M = \frac{0.06}{2} = 0.03[/tex]

How many people do you need to have in your study?

This is n for which M = 0.03. So

[tex]M = z\frac{\sigma}{\sqrt{n}}[/tex]

[tex]0.03 = 1.88\frac{0.37}{\sqrt{n}}[/tex]

[tex]0.03\sqrt{n} = 1.88*0.37[/tex]

[tex]\sqrt{n} = \frac{1.88*0.37}{0.03}[/tex]

[tex](\sqrt{n})^2 = (\frac{1.88*0.37}{0.03})^2[/tex]

[tex]n = 537.6[/tex]

Rounding up:

You need to have 538 people in your study.


Related Questions

Pete's Pizza has a mean delivery time of 29 minutes with a standard deviation of 3 minutes. Determine the z-score for the number of pizzas delivered in less than 25 minutes.

Answers

Answer:

9 pizzas

Step-by-step explanation:

the right aswer is -1.33

A recipe for pancakes requires 3/4 cup of oil. If Mr. Darcy wants to triple the recipe, how much oil will he need?

Answers

Answer:

the answer is 2 1/4 cups of oil

Step-by-step explanation:

if he wants to triple the ingredient then you would triple the numerator and than simplify your new fraction

3 times 3 is 9 = 9/4

9 divided by 4 is 2.25 = 0.25 is equal to 1/4 so it would be 2 1/4 cups of oil

Find the area of the composite figure.
A. 122.5 sq ft
B. 171.5 sq ft
C. 196 sq ft
D. 296. 5 sq ft

Answers

Answer:

I think B is your answer if so then comment me and you can mark me as brainliest and please follow me


[tex] \large \sf \blue{Find \: the \: H.C.F \: of : }[/tex]
[tex] \sf \purple{➪ \: 84 \: and \: 156}[/tex]

Answers

Answer:

[tex] \large \sf \blue{Find \: the \: H.C.F \: of : }[/tex]

[tex] \sf \purple{➪ \: 84 \: and \: 156}[/tex]

2x^2-13=x Write the quadratic equation in standard form:

Answers

Answer:

2xˆ2-x-13=0

Step-by-step explanation:

Answer:

Below.

Step-by-step explanation:

2x^2 - 13 = x

Subtract x from both sides:

2x^2 - x - 13 = 0 is the standard form.

jaslyyyyyyyyyyyyyyyy is good girl :3

Answers

Answer:

7/9

Step-by-step explanation:

this equation is true:

21/27 = 7/9

If the numerator is greater than or equal to the denominator of a fraction, then it is called an improper fraction. In that case, you could convert it into a whole number or mixed number fraction.

7/9 = Proper Fraction

Hey does anyone please can help me with this

Answers

Answer:

Step-by-step explanation:

PLEASE HELP! I feel horrible and I'm crying so hard right now. This is due.

Answers

Answer:

62

Step-by-step explanation:

surface area of a rectangular prism = 2lw + 2lh + 2wh

Where l = length, w = width and h = height

The box has the following dimensions

length = 5 in

width = 3 in

height 2 in

Using these dimensions, we plug in the values into the formula

[tex]SA=2(5*3)+2(5*2)+2(3*2)\\5*3=15\\15*2=30\\5*2=10\\10*2=20\\3*2=6\\6*2=12\\SA=30+20+12\\30+20+12=62[/tex]

Hence, the surface area = 62

PLZZZZZZZZZZZZZZZZZ help

Answers

Answer:

true

Step-by-step explanation:

[tex]\frac{x}{2} <20[/tex]

* substitute 30 for x *

[tex]\frac{30}{2} <20\\\frac{30}{2} =15\\[/tex]

we're left with 15 < 20 which is true

dele took 25 minutes to walk to school and he arrived at exactly 8:00am, at what time did he leave his home​

Answers

i think it would be around 7:30am

g The least-squares regression line of the number of visitors, y, at a national park and the temperature, x, is modeled by the equation . What is the predicted number of visitors when the temperature is 78o? 10.3 visitors 85.2 visitors 95.5 visitors 888.6 visitors 6,655.9 visitors

Answers

Answer: D) 888.6

Step-by-step explanation:

The expression which would help arrive at the required answer is y = 78b + c.

The least regression equation is the equation of best fit obtained from a linear regression graph.

The linear regression equation is expressed in the form :

y = bx + c ; where ;

y = Predicted variable

x = predictor variable

c = intercept

b = slope

The least regression equation is not given in the question above.

However, we could give the equation in the linear regression format :

y = number of visitors

y = number of visitors x = temperature = 78°

Hence, the equation becomes :

y = b(78) + c

y = 78b + c

Inputting the values of b and c in the equation will give the required answer.

Learn more : https://brainly.com/question/4997238?referrer=searchResults

Angle Relationships

A water slide is a straight ramp 25 m long that starts from the top of a tower. If the angle the slide forms with the top of the tower is 33°. determine the height of the tower. Round your answer to the nearest meter.

a. 30 m
b. 25 m
c. 24 m
d. 21 m

Pleases elect the best answer from the choices provided

Answers

Answer:

D. 21 m

Step-by-step explanation:

I calculated it logically

Which function rule represents the data in the table?

x –3 –2 –1 0 1
y 1 –2 –5 –8 –11

A. y = –3x – 8
B. y = one-third x – 8
C. y = one-third x + 8
D. y = 3x + 8

Answers

B

Step-by-step explanation:

How much money would you have in an account after 15 years if you earned 9,3% annually and you started with R573,00?​

Answers

Given:

Principal = R573.00

Rate of interest = 9.3% annually

Time = 15 years.

To find:

The amount after 15 years.

Solution:

Formula for amount is:

[tex]A=P\left(1+\dfrac{r}{n}\right)^{nt}[/tex]

Where, P is principal, r is the rate of interest in decimal, n is the number of time interest compounded in an year and t be the number of years.

The interest is compounded annually, so n=1.

Putting [tex]P=573,r=0.093,n=1,t=15[/tex] in the above formula, we get

[tex]A=573\left(1+\dfrac{0.093}{1}\right)^{1(15)}[/tex]

[tex]A=573\left(1+0.093\right)^{15}[/tex]

[tex]A=573\left(1.093\right)^{15}[/tex]

[tex]A=2174.98893[/tex]

[tex]A\approx 2174.99[/tex]

Therefore, the amount in the account after 15 years is about  R2174.99.

How many feet are in 5 yards

Answers

Answer:

15 feet

Step-by-step explanation:

Forumula: Multiply the length value by 3.

5*3= 15 feet

Hope this  helped! :)

Answer:

15 feet

Step-by-step explanation:

okay so in 1 yard is 3 feet

is it is 5 yards so there is 15 feet

If x = 4, calculate the value of: 7x + 2x + x

Answers

Answer:

40

Step-by-step explanation:

7(4)+2(4)+(4)=?

28+8+4=?

36+4=?

40

7x+2x+x

Simplify

(7+2+1)x10x

Put x=4

10(4)40

• I am a fraction less than 1.
My denominator is a multiple of 5.
My denominator is less than 20.
• My numerator is a multiple of 4.
My numerator is 3 less than my
denominator.

Answers

Answer:

12/15

Step-by-step explanation:

3x5=15

4x3=12

15-12=3

Therefore the answer is 12 over 15

A. 20
b. 5
c. 40
d. 45

Answers

Answer:

C, 40

Step-by-step explanation:

You can set up the equation as 20+4x=180

180 is the total angle of the line

4x=160 and divide each side by 4

x=40

I think it could be B

By divide but iam not sure sorry if it wronge

another khan academy pls

Answers

Answer:

89

Step-by-step explanation:

3 consecutive numbers can be:

[tex]x-1, x, x+1[/tex] ; for example: 1, 2, 3 (1 is 1 less than 2, and 3 is 1 more than 2)

The sum is all of them added, so

[tex]x-1+x+x+1=270; 3x=270; x=90[/tex]

90 is the middle number though, so the first number is 89

Answer:

88, 90, 92

Step-by-step explanation:

I hop this is right can you pls answer this question khan academy.

Rectangle ABCDABCDA, B, C, D is graphed in the coordinate plane. The following are the vertices of the rectangle: A(2, -6),A(2,−6),A, left parenthesis, 2, comma, minus, 6, right parenthesis, comma B(5, -6)B(5,−6)B, left parenthesis, 5, comma, minus, 6, right parenthesis, C(5, -2)C(5,−2)C, left parenthesis, 5, comma, minus, 2, right parenthesis, and D(2, -2)D(2,−2)D, left parenthesis, 2, comma, minus, 2, right parenthesis.

What is the perimeter of rectangle ABCDABCDA, B, C, D?

units

Thank you

12 Select the correct answer from each drop-down menu. 4 units 6 units 4 units NIE bi TH 6 units 4 units The total area of the three triangles is square units. The area of the figure is square units. Reset​

Answers

Answer:

Area of three triangles = 36 square units

Area of the composite figure = 60 square units

Step-by-step explanation:

Area of a triangle = [tex]\frac{1}{2}(\text{Base})(\text{Height})[/tex]

Area of ΔABC = [tex]\frac{1}{2}(6)(4)[/tex]

                        = 12 square units

Area of ΔCDE = [tex]\frac{1}{2}(4)(6)[/tex]

                        = 12 square units

Area of ΔGEF = [tex]\frac{1}{2}(6)(4)[/tex]

                       = 12 square units

Area of rectangle ACEG = Length × Width

                                        = AC × CE

                                        = 6 × 4

                                        = 24 square units

Area of three triangles = 12 + 12 + 12

                                      = 36 square units

Area of the composite figure = Area of three triangles + Area of the rectangle

= 36 + 24

= 60 square units

Answer:

The total area of the three triangles is 36 square units.

The area of the figure is 60 square units.

Step-by-step explanation:

PLEASE HELLLLLLP NO FAKE ANSWERS

Answers

Answer: p= -3,2

q= -3,8

R= -8,8

s=-8,2

Step-by-step explanation:

If there are 7 red candies in a bag of 36 colored candies, what is the probability of getting a red candy as a
percent? Round to the nearest whole percent.PLS HELP THIS IS FOR A TEST

A.19%

b. 29%

C.50%

d. 70%

Answers

Answer:

19.4% but rounded is 19%

Step-by-step explanation:

7/36 = x/100

36x = 700 (cross multiply)

36x/36 = 70036

x = 19.4444444

1/6 + 2/3 + 36 (help plz)

Answers

1/6+2/3+36= 221/6 or simplified 36 5/6
221/6 simplified, 36 5/6 as a mixed number, 36.83 as a decimal

Please help out. The question is on the photo

Answers

Answer:

55

Step-by-step explanation:

A spinner has 10 equal sections: 3 redsections, 4 green sections and 3 bluesections. If Josh spins the spinner, what isthe probability that it lands on a greensection?

Answers

40% chance I think let me know if this is right or not

Look at picture and find the value of x please help no links!!

Answers

The best answer to go with is c

2.- Un campesino guarda un doceavo de su trigo cosechado para semilla, un sexto de la misma
cosecha lo convierte en harina y vende 288 kilos. ¿Cuántos kilogramos de trigo cosechó?

Answers

please translate in english

Calculate the radius or diameter in each of the following problems.

1) d = 8.3 mm
Calculate the radius of the circle.

Answers

Answer:

4.15

Step-by-step explanation:

the radius is half the diameter so 8.3/2

=4.15mm

Answer:

4.15

Step-by-step explanation:

radius is the half of the diameter so 8.3/2 is 4.15

Find the inverse function.

Answers

(x+1)^3 is the answer
It should be....
(x-1)^3

Please correct me if i am wrong.

A population has a standard deviation of 20.2. What is the standard error of
the sampling distribution if the sample size is 144? Round your answer to two
decimal places.
A) 1.68
B) 1.84
C) 1.55
D) 1.44

Answers

Answer: 1.68

Step-by-step explanation:

A pex

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