Suppose you are a civil engineer, specializing in traffic volume control for the City of Grand Rapids. Your department has been receiving a multitude of complaints about traffic wait times for a certain intersection in the heart of downtown. To see if these claims are valid, you want to monitor the true average wait time at that intersection. Over the course of a few months, you record the average number of minutes a car waits at the intersection between 4:00 PM and 5:00 PM. With a sample size of 9 cars, the average wait time is 6.79 minutes with a standard deviation of 2.2175 minutes. Construct a 99% confidence interval for the true average wait time for a car at the intersection between 4:00 PM and 5:00 PM.

Answers

Answer 1

Answer:

(4.31 ; 9.27)

Step-by-step explanation:

Given :

Sample size , n = 9

Mean, x = 6.79

Standard deviation = 2.2175

The confidence interval :

Xbar ± Margin of error

Margin of Error = Zcritical * s/√n

Zcritical at 99% ; df = n - 1 = 9 - 1 = 8 = 2

Zcritical at 99% = 3.355

Margin of Error = 3.355 * 2.2175/√9 = 2.480

Lower boundary = 6.79 - 2.480 = 4.31

Upper boundary = 6.79 + 2.480 = 9.27

(4.31 ; 9.27)


Related Questions

PLEASE HELP!!
The batteries from a certain manufacturer have a mean lifetime of 860 hours, with a standard deviation of 70 hours. Assuming that the lifetimes are normally
distributed, complete the following statements.
(a) Approximately of the batteries have lifetimes between 790 hours and
930 hours.
Example
(b) Approximately 95% of the batteries have lifetimes between hours and
hours.

Answers

Answer:

A) 99.74%

B) 633.6 hours and 986.4 hours

Step-by-step explanation:

Solution :

Given that ,

mean =  u =810

standard deviation = sigma  = 90    

P(540< x <1080 ) = P[(540-810) /90 < (x - u   ) /  sigma < (1080-810) /90 )]

= P( -3< Z < 3)

= P(Z <3 ) - P(Z < -3)

Using z table    

=0.9987-0.0013

= 0.9974

answer=99.74%

(B)

middle 95% of score is

P(-z < Z < z) = 0.95

P(Z < z) - P(Z < -z) = 0.95

2 P(Z < z) - 1 = 0.95

2 P(Z < z) = 1 + 0. 95= 1.95

P(Z < z) = 1.95/ 2 = 0.975

P(Z <1.96 ) = 0.975

z  ±1.96    

Using z-score formula  

x= z * sigma  +  u

x= -1.96* 90+810

x= 633.6

Using z-score formula  

x= z * sigma  +  u

x=1.96* 90+810

x= 986.4

633.6 hours and 986.4 hours

Karrie is 24 years old. She took her age, divided by -3, added -7, then
multiplied by -4. Her result is 2 years older than her father's age. How old is
Karrie's father? *

Answers

Answer:

58 years old

Step-by-step explanation:

24/-3 is -8

-8+-7 is -15

-15*-4 is 60

60-2 is 58

help me please I have to pass​

Answers

Answer:

Step-by-step explanation:

15% of 400

15/100*400

15*400/100

6000/100

60

therefore ur answer is 60

C. 60 ✅

[tex]\large\mathfrak{{\pmb{\underline{\red{Step-by-step\:explanation}}{\orange{:}}}}}[/tex]

[tex] \frac{15}{100} \times 400 \\ =15 \times 4 \\ = 60 [/tex]

[tex]\large\mathfrak{{\pmb{\underline{\orange{Happy\:learning }}{\orange{.}}}}}[/tex]

One half of one tenth is what fraction?

Answers

Answer:

1/2  1/100

Step-by-step explanation:

One half of one tenth is  [tex]\frac{1}{20}[/tex] fraction.

What is a fraction?

A number that expresses parts of a whole object or a set of objects is known as a fraction.

Given

One half of one tenth

Rewriting in mathematical form

= [tex]\frac{1}{2} (\frac{1}{10} )[/tex]

= [tex]\frac{1}{20}[/tex]

Hence, One half of one tenth is  [tex]\frac{1}{20}[/tex] fraction.

Learn more about fraction here

https://brainly.com/question/10708469

#SPJ2

A rectangular prism has a length of 5 meters, a width of 6 meters, and a height of 3 meters.
What is the volume of the prism?

Pls hurry
Give Brainlyest

Answers

90 meters
6 x 5=30
30 x 3= 90

volume = length x width x height

volume = 5m x 6m x 3m = 90 m³

What is the answer for the diagram?

Answers

Answer:

1340-

Step-by-step explanation:

A population of 950 bacteria grows continuously at a rate of 4.75% per day.
Write an exponential function, N (t ), that represents the bacterial population after t days.

Answers

860N(t) would be the answer just divide the percentage with the population

Solve the inequity -3y + 80 > 110

Answers

Answer: y<-10

Step-by-step explanation:

i hope this help :)

Answer:

y<-10

Step-by-step explanation:

-3y+80>110

     -80  -80

-3y>30

-y>10

y<-10  (when deviding by a negative, > switches to <)


a square is 44 metre long its perimeter is ​

Answers

Answer:

Answer. = 176 m sq.

Step-by-step explanation:

Hope it helps you

Have a nice day

176 m my friend atleast I think that’s what it is

the object is a circle with a pentagon inside of it each of the sides of the pentagon is a chord of the circle

Answers

Answer:

The answer to ur question should be, A Object A

Answer:

a

Step-by-step explanation:

Given a variance of 1992.8, what is the standard deviation?


about 44.64


about 43.13


about 43.76


about 45.20

Answers

Answer:

About 44.64.

Step-by-step explanation:

Variance and standard deviation:

The standard deviation is the square root of the variance.

In this question:

Variance of 1992.8. So

[tex]s = \sqrt{1992.8} = 44.64[/tex]

So about 44.64.

i Illustrative Mathematid Kendall Hu Ant Trek The distance between Los Angeles and New York City is about 3,944 km. An ant can run about 18 mm per second. How long would it take an ant to run from Los Angeles to New York City?​

Answers

You have to multiply all of them together and then get your answer

Laurel used 12 1/2 Square feet of cloth to make three dresses how many square feet of cloth required to make 12 similar dresses?

Answers

Answer:

150 square feet

Step-by-step explanation:

12 1/2 * 12 = 150

Find the multiplicative inverse of:

[tex]4 \times \frac{ - 7}{8} [/tex]
[tex] \frac{ - 5}{6} \times \frac{2}{7} [/tex]

Answers

Answer:

Step-by-step explanation:

first no answer=1/4*8/-7 =8/-28

second no answer=6/-5*7/2 =42/-10

help me pass thank you!!!

Answers

Answer:

64

Step-by-step explanation:

[tex] (\frac{m^{2} }{m + 3} )^{3} \\ = \frac{m^{6} }{(m + 3)^{3} } \\ = \frac{6 {}^{6} }{{9 {}^{3} } } [/tex]

46656/729

= 64

in a school , 4/9 of the students are boys and number of girls is 90 . find the number of boys in school

Answers

4/9 of the students are boys thus 5/9 students are girls.

Let " x " be the number of all students.

So we have :

5/9 × x = 90

Multiply both sides by 9/5

5/9 × 9/5 × x = 90 × 9/5

1 × x = 9 × 9 × 10 × 1/5

x = 81 × 2

x = 162

_______________________________

number of boys = 4/9 × x

n o boys = 4/9 × 162

n o boys = 162/9 × 4

n o boys = 18 × 4

n o boys = 72

How to solve x/7 = 7

Answers

Answer:

x = 49

Step-by-step explanation:

x/7 = 7

Multiply each side by 7

7* x/7 =7* 7

x = 49

Sami made 23,400 last year in income from his job. He worked 30 hours per week and worked all 52 weeks of the year. What was his hourly pay rate?

Answers

Answer:

$15 per hour

Step-by-step explanation:

30 hours per week x 52 weeks in a year = 1560 hours per year

23,400 / 1560 = $15 per hour

How can we represent three-dimensional figures in only two dimensions?

Answers

just add , multiply .

Answer: A three-dimensional figure has a length, a width, and a height. A net is a two-dimensional pattern of a three-dimensional figure, that can be folded to form the figure. Identify the net that we could fold in order to create this 3D figure. Match the 3D figure to the right with its appropriate net, below.

How many square feet is the world's largest pizza, including the crust?
(Be sure to show and/or explain your work, make your final answer clear, and include units)
The worlds largest pizza, including the crust, has a length of 131 feet

Answers

Answer:

The largest pizza has a total surface area of 1,261.65 m² (13,580.28 ft²) and was prepared by Dovilio Nardi, Andrea Mannocchi, Marco Nardi, Matteo Nardi and Matteo Giannotte (all Italy) from NIPfood at Fiera Roma, in Rome, Italy, on 13 December 2012.

Step-by-step explanation:

PLEASE HELP I WILL MARK BRAINLIST

Answers

Answer:

the are would be 18

Step-by-step explanation:

bc 2x3=6 and then 4x3=12 so 12+6=18

Area of square + area of rectangle = area of whole figure
2 *2 + 2( 4 x 3 ) = 4+ 24= 28in*2

A bag contains 8 red pens, 7 blue pens, and 14 black pens. Denato wants to pull a blue pen from the bag. What is the sample space for this experiment? 1. Blue, Red 2. Blue 3. Red, Blue, Black 4. Red, Black

Answers

2...............blue

Answer:

Red and blue is the correct answer

Step-by-step explanation:

Find the median of the data.
93.81.94.71.89.92.94.99
The median is
Find the mode(s) of the data,

Answers

Step-by-step explanation:

MEDIAN

71, 81, 89, 92, 93, 94, 94, 99

92 + 93 = 185 / 2 = 92.5

The median is 92.5

MODE

71, 81, 89, 92, 93, 94, 94, 99

The mode is 94

f(x) = –?
+ x
Find f(-1)

Answers

Answer:

Replace the variable x with −1

in the expression.

f(−1)=−(−1)²−1

Simplify −(−1)²−1.

Remove parentheses.

−(−1)²−1

Multiply −1 by (−1)²

by adding the exponents.

(−1)³−1

Raise −1 to the power of 3.

−1−1

Subtract 1 from −1.

−2

Step-by-step explanation:

Hope it's right

the perimeter of a rectangle is 90m. The length is three less than five times the width. What is the length and the width of the rectangle?

Answers

Answer:

length : 37 m

width : 8 m

Step-by-step explanation:

perimeter = 2×l(ength) + 2×w(idth) = 90

l = 5w - 3

=> 2×(5w-3) + 2w = 90

10w - 6 + 2w = 90

12w = 96

w = 8

=> l = 5w - 3 = 5×8 -3 = 40-3 = 37

Evaluate the expression when x=7 and y=-3. 5y2-x

Answers

-37. You multiply first

A right circular conical tank of height 1 foot and radius 1 foot at the top is full of water. Taking the density of the water to be 60 pounds per cubic foot, how much work in foot-pounds is required to pump all the water up and over the top of the tank

Answers

Answer:

Step-by-step explanation:

Height= 1 foot

Radius= 1 foot

Density= 60 pounds per cubic foot

Density = mass/ volume

Vol of cone= 1/3× 22/7 ×(radius^2)

=1/3×22/7×1×1

=22/21

Mass=volume × density

= 22/21 × 60

=440/7

Energy = mgh

= 440/7 ×10 × 1

= 628.57 foot pounds

Only please help #2,3,5, and 6

Answers

2) 7:9
3)5.30/6= 0.88
5)3:4
6)a) 15:20 and to simply divide by 5 to get 3:4
b)the amount saved is 5 (20-15) so the first ratio is 5:20 and to simplify divide 5 to get 1:4

Answer:

3.$0.9

5.9:3 =3:1

Step-by-step explanation:

3.$5.40÷6=$0.9

pls i need help i’ll give brainliest!

Answers

9514 1404 393

Answer:

  x = 12

Step-by-step explanation:

The rule here is that the product of the lengths from the external point of intersection (angle vertex) to the intersections with the circle is the same for both secants. The tangent counts as intersecting the circle twice. So, we have ...

  (6)(6) = (3)(x)

  x = 36/3 = 12 . . . . . divide by the coefficient of x

PLEASE HELP
Makayla owns a small business selling used books. She knows that in the last week 58 customers paid cash, 25 customers used a debit card, and 2 customers used a credit card.
Based on these results, express the probability that the next customer will pay with a debit card as a fraction in simplest form.

Answers

Answer:

2/5 :)

Step-by-step explanation:

58+2=60+25=85-25=60 60 = 2/5

The solution is 5/17

The probability that the next customer will pay with a debit card is given by the equation A = 5/17

What is Probability?

The probability that an event will occur is measured by the ratio of favorable examples to the total number of situations possible

The value of probability lies between 0 and 1

Given data ,

Let the probability that the next customer will pay with a debit card be A

Now , the equation will be

The number of customers who paid cash last week = 58 customers

The number of customers who used debit card last week = 25 customers

The number of customers who used credit card last week = 2 customer

So ,

The total number of customers = 58 + 25 + 2

The total number of customers = 85 customers

Now , the probability that the next customer will pay with a debit card A = number of customers who used debit card last week / total number of customers

Substituting the values in the equation , we get

Probability that the next customer will pay with a debit card A = 25 / 85

On simplifying the equation , we get

Probability that the next customer will pay with a debit card A = 5 / 17

Therefore , the value of A is 5/17

Hence , the probability is 5/17

To learn more about probability click :

https://brainly.com/question/17089724

#SPJ2

Other Questions
is reinvented a positive or negative word? find the value of x. please help! :) Lilly went shopping with her mother. She took $48.95 with her to spend. She spent $23.57 at one store. How much money did she have left? If AB is parallel to CD and the slope of CD is-5, what is the slope of AB?O A.01B.1C. -5D. 5 When light is refracted A. it changes its direction as it passes into a new medium. B. it changes it direction and stays in the same medium. C. it keeps moving in the same direction as it passes into a new medium. D. it is absorbed as it strikes the surface of a new medium. ONE specific historical event or development that accounts for the changes in United States energy sources between 1850 and 1900. You need to pick up a book off the floor and place it on a tabletop. You do 1.56J of work to lift the book with a force of 300N. What is the distance? what is acid? Explain it Select statements about Multiprocessors that are FALSE. a. Asymmetric multiprocessors are a popular form of tightly coupled architecture b. Symmetric multiprocessors are a popular form of tightly coupled architecture c. Tightly coupled multiprocessors share a single centralized memory, which requires an operating system to synchronize processes carefully to ensure protection d. Loosely coupled multiprocessors have a physically distributed memory and are also known as distributed systems cual es la formacin filosfica de los japoneses?? In the figure below, PQR and TQS are vertical angles. What is the value of x? *A. 16B. 32C. 48D. 66 a diamond poem for economy Find the distance between the points (1, 4) and (- 2, - 1). How does Travis describe his current situation? Pure magnesium metal is often found as ribbons and can easily burn in the presence of oxygen. When 3.31 g of magnesium ribbon burns with 8.45 g of oxygen, a bright, white light and a white, powdery product are formed. Enter the balanced chemical equation for this reaction. Be sure to include all physical states. PLEASEEE HELP I WILL MARK BRAINLIESTTTT!!! (NO LINKS)Describe how the data is dispersed in a box plot with the following data set: 25, 36, 21, 30, 20, 32, 38, 19, 36, 31, 26, 33, 27, 18, 24. Escoge la opcin correcta.Algunos pases no tienen elecciones directas;los candidatos votan por representantes y estos eligen al presidentelos votantes eligen a un presidente y este elige a los representanteslos votantes eligen a representantes y estos votan por los candidatoslos ciudadanos votan por los candidatos y estos eligen al presidente Simplify and give me steps please.(5m^4/3 x 5n^1/4) (m^1/3 x 2n^1/8) Can someone help me?? "hanggang ako'y wala't nakikipaghamok, nag-aapuhap ka ng pang-aliw-loob; manalo man ako'y kung bagong nanasok nakikita mo na'y may dala pang takot" kahuluganflorante at laura