Suppose taxi fares from Logan Airport to downtown Boston is known to be normally distributed and a sample of seven taxi fares produces a mean fare of $21.51 and a 95% confidence interval of [$20.52, $22.48]. Which of the following statements is a valid interpretation of the confidence interval?
a. we are 95% confident that a randomly selected taxi fare will be between $2051 and $2421.
b. 95% of all taxi fares are between $2051 and $2421.
c. We are 95% confident that the average tau fare between Logan Airport and downtown Boston will fall between $2051 and $2421.
d. The mean amount of a taxi fare is $22.31, 95% of the time.

Answers

Answer 1

Answer:

c. We are 95% confident that the average taxi fare between Logan Airport and downtown Boston will fall between $20.51 and $24.21.

Step-by-step explanation:

x% confidence interval:

A confidence interval is built from a sample, has bounds a and b, and has a confidence level of x%. It means that we are x% confident that the population mean is between a and b.

95% confidence interval of [$20.52, $22.48].

We can be 95% sure that the true mean amount of taxis fares in downtown Boston is in this interval, and thus, the correct answer is given by option C.


Related Questions

The length of a rectangle is 19 centimeters less than its width. Its area is 20 square centimeters. Find the dimensions of the rectangle. Use the​ formula, area =length*width.

Answers

Answer:

width =20

length = 1

Step-by-step explanation:

length = w - 19

A = l*w

20 = (w-19) * w

20 = w^2 - 19w

Subtract 20 from each side

0 = w^2 - 19w - 20

Factor

0 = (w+1)(w-20)

Using the zero product property

w+1 = 0 w-20 = 0

w = -1   w=20

Widths cannot be negative

w=20

l = 20-19 = 1

On a coordinate plane, a curved line begins at point (negative 2, negative 3), crosses the y-axis at (0, negative .25), and the x-axis at (1, 0).
What is the domain of the function on the graph?

Answers

Answer:

Option D

Step-by-step explanation:

correct answer on edge :)

Answer:

D <3

Step-by-step explanation:

Tara created a 1 inch cube out of paper.
1 in
If she doubles the volume of her cube, which statement could be true?
A Tara added two inches to the height, length and width of the cube.
B Tara added two inches to the height of the cube.
C Tara doubled the measurements of the cube's height, length and width.
D Tara doubled the measurement of the cube's height.

Answers

Answer:

answer D

Step-by-step explanation:

V=L*W*H=1 ==> L=1,W=1,H=1

A:

L-> L+2=1+2=3

W -> W+2 = 1+2=3

H -> H+2=1+2=3

V=3*3*3=27 not the doubled of the volume's cube

A is false

B:

H -> H+2=1+2=3

V=1*1*3=3 not the doubled of the volume's cube

B is false

C:

H -> 2*H=2*1=2

L -> 2*L=2*1=2

W -> 2*W = 2*1=2

V=2*2*2=8 not the doubled of the volume's cube

C is false

D:

H-> H*2=1*2=2

L=1

W=1

V=1*1*2=2 is the doubled of the volume's cube

D is true

Help please. There’s a 4th option just couldn’t fit it in the photo

Answers

Answer:

Line A

Step-by-step explanation:

graph it

A random sample of medical files is used to estimate the proportion p of all people who have blood type B. (a) If you have no pre-liminary estimate for p, how many medical files should you include in a random sample in order to be 90% sure that the point estimate will be within a distance of 0.03 from p?(b) Answer part (a) if you use the pre-liminary estimate that about 13 out of 90 people have blood type B.

Answers

Answer:

a) 752 medical files should be included.

b) 372 medical files should be included.

Step-by-step explanation:

In a sample with a number n of people surveyed with a probability of a success of [tex]\pi[/tex], and a confidence level of [tex]1-\alpha[/tex], we have the following confidence interval of proportions.

[tex]\pi \pm z\sqrt{\frac{\pi(1-\pi)}{n}}[/tex]

In which

z is the z-score that has a p-value of [tex]1 - \frac{\alpha}{2}[/tex].

The margin of error is of:

[tex]M = z\sqrt{\frac{\pi(1-\pi)}{n}}[/tex]

90% confidence level

So [tex]\alpha = 0.1[/tex], z is the value of Z that has a p-value of [tex]1 - \frac{0.1}{2} = 0.95[/tex], so [tex]Z = 1.645[/tex].

Question a:

This is n for which M = 0.03. We have no estimate, so we use [tex]\pi = 0.5[/tex]. So

[tex]M = z\sqrt{\frac{\pi(1-\pi)}{n}}[/tex]

[tex]0.03 = 1.645\sqrt{\frac{0.5*0.5}{n}}[/tex]

[tex]0.03\sqrt{n} = 1.645*0.5[/tex]

[tex]\sqrt{n} = \frac{1.645*0.5}{0.03}[/tex]

[tex](\sqrt{n})^2 = (\frac{1.645*0.5}{0.03})^2[/tex]

[tex]n = 751.67[/tex]

Rounding up:

752 medical files should be included.

Question b:

Now we have that:

[tex]\pi = \frac{13}{90} = 0.1444[/tex]

So

[tex]M = z\sqrt{\frac{\pi(1-\pi)}{n}}[/tex]

[tex]0.03 = 1.645\sqrt{\frac{0.1444*0.8556}{n}}[/tex]

[tex]0.03\sqrt{n} = 1.645\sqrt{0.1444*0.8556}[/tex]

[tex]\sqrt{n} = \frac{1.645\sqrt{0.1444*0.8556}}{0.03}[/tex]

[tex](\sqrt{n})^2 = (\frac{1.645\sqrt{0.1444*0.8556}}{0.03})^2[/tex]

[tex]n = 371.5[/tex]

Rounding up:

372 medical files should be included.

A line contains the points R (-1, 8) S (1, 4) and T (6, y). Solve for y. Be sure to show and explain all work.

Answers

Given:

A line contains the points R(-1, 8), S(1, 4) and T(6, y).

To find:

The value of y.

Solution:

Three points are collinear if:

[tex]x_1(y_2-y_3)+x_2(y_3-y_2)+x_3(y_1-y_2)=0[/tex]

A line contains the points R(-1, 8), S(1, 4) and T(6, y). It means, these points are collinear.

[tex]-1(4-y)+1(y-8)+6(8-4)=0[/tex]

[tex]-4+y+y-8+48-24=0[/tex]

[tex]2y+12=0[/tex]

Subtract 12 from both sides.

[tex]2y=-12[/tex]

Divide both sides by 2.

[tex]y=\dfrac{-12}{2}[/tex]

[tex]y=-6[/tex]

Therefore, the value of y is -6.

Answer: The guy above me is right

Step-by-step explanation: I took the test and got it right

Help if possible pls

Answers

Answer: Oh heaven nah

Step-by-step explanation: Lord have mercy

if the two linear functions are represented two different forms the _____ is used to compare the steepness of the two functions>

Answers

Answer:

Slope

Step-by-step explanation:

Given

The above statement

Required

What compares the steep of linear functions

Literally, steepness means slope.

So, when the slope of the two linear functions are calculated, we can make comparison between the calculated slopes to determine which of the functions is steeper or less steep.

Also:

Higher slope means steeper line

e.g.

4 is steeper than 1

You are reading a study which asked 60 students enrolled in the local high school to self-report drug use, sexual activity and college education plans. You know this is an example of what type of sampling methodology

Answers

Answer:

Convenience sampling method

Step-by-step explanation:

We can see that these students are not selected randomly.

You know this is an example of the convenience sampling method. The convenience sampling method can be described as a non probability method of sampling that is also from people that can be easily contacted. These people are sampled basically for the fact that they are convenient ways of getting data, for the person who is researching. The first available source of primary data is what is used and there are no other requirements for getting this participants.

Which of these is an example of a continuous random variable?
A. Number of flights leaving an airport
B. Pieces of mail in your mailbox
C. Attendance at a sporting event
D. Time to run a race

Answers

Answer:

continues means that can be written in decimal like weight,height, distance(5.44km)

I think its D. is time decimal? Gods plan.

i need help. i will give brainiest as soon as possible

Answers

Answer:

B

Step-by-step explanation:

Let me know if you need an explanation.

Answer:

B

Step-by-step explanation:

4x^3+x^2+5x+2

4x^3 cannot cancel with others= 4x^3

4x^2-3x^2= x^2

5x cannot cancel with others= 5x

-3+5= 2

4x^3+x^2+5x+2

Red Top Cab Company receives multiple complaints per day about driver behavior. Over 8 days the owner recorded the number of calls to be 3, 0, 8, 9, 6, 7, 9, and 8. What is the lower control limit for the 3-sigma c-chart?a. 13.35.
b. 0.
c. 9.03.
d. 24.
e. 8.45.

Answers

Answer:

-1.25

Step-by-step explanation:

The lower control limit for the 3 sigma c chart is :

cbar - 3√cbar

central line = cbar = Σc / n

n = size

Given the data :

3, 0, 8, 9, 6, 7, 9, 8

Σc = 50

n = 8

cbar = 50/8

cbar = 6.25

Lower Control Limit = cbar - 3√cbar

Lower Control Limit = 6.25 - 3√6.25

Lower control limit = 6.25 - 7.5

Lower control limit = -1.25

Question 4 of 10
If A = (-1,-3) and B = (11,-8), what is the length of AB?
A. 12 units
B. 11 units
C. 14 units
D. 13 units
SUBMIT

Answers

Step-by-step explanation:

AB = square root of [(xA-xB)^2+(yA-yB)^2]

AB=Squarerootof(-1-11)^2 +(-3-(-8))^2=Squarerootof(-12)^2+(5)^2)

AB=Squarerootof((144)+25)= Squarerootof(169)=13 the answer is 13 units

The choice D is the right one

Help on this math question please

Answers

Answer:

3x² + x + 1

-3x² + x + 1

-54

Step-by-step explanation:

there is nothing complicated to it. you just use the requested pertain on the whole expressions of the functions, and the result is then the new function.

so,

r(x) = 3x²

s(x) = x + 1

what do you think s + r is ?

it is simply

(s+r)(x) = 3x² + x + 1

done. that is really all there is to this.

now the next (but consider the sequence due to the sign)

(s-r)(x) = x + 1 - 3x² = -3x² + x + 1

and the third

(s×r)(x) = 3x²(x+1) = 3x³ + 3x²

so, for x=-3

(s×r)(-3) = 3×(-3)³ + 3×(-3)²

remember, an even power of a negative number gives a positive result, an uneven power of a negative number gives a negative result.

(s×r)(x) = 3×-27 + 3×9 = -81 + 27 = -54

Which graph represents a line with a slope of -2/3 and a y-intercept equal to that of the line y=2/3x - 2

Answers

Answer: The image shown in your question as well as the one I provided is the correct answer

Step-by-step explanation:

a line with a slope of 2/3 must mean that the "m" is 2/3

y = mx + b

y = 2/3x + b

The question calls for the y-intercept to be equal to that of y=2/3x - 2

using the given equation, we easily figure out -2 is the y-intercept

so the line must go through (0,-2).

Which statement is true about the expression 12- 7 + 3?

Answers

Answer:

I don't see any statements here.

Anyway, the answer is 8.

[tex]12 - 7 + 3 = 8[/tex]

Jerry tosses a coin 17 times and makes one step forward with each toss. However, he makes three more steps forward if he gets heads. If he made 62 steps forward, how many heads did he get?

Answers

The answer is 15, because if you subtract 62 by 17 then you’ll get 45 then you are divided by three to get 15. Have a nice day!!! I hope this helped!!!

The the intensity I of light (in lumens) in a certain lake at a depth of x feet is given by log(1/12) = -0.00235x. What is the intensity of the light (in lumens) at a depth of 20 feet? Round your answer to the nearest hundredth and label 1 your answer.​

Answers

Answer:

11.45 lumens

Step-by-step explanation:

We are given that

[tex]log(I/12)=-0.00235x[/tex]

Where x=Depth

I=Intensity of light

We have to find the intensity of the light at a depth of 20 feet.

Substitute the value of x

[tex]log(I/12)=-0.00235\times 20[/tex]

[tex]log(I/12)=-0.047[/tex]

[tex]\frac{I}{12}=e^{-0.047}[/tex]

[tex]I=12e^{-0.047}[/tex]

[tex]I=11.45 Lumens[/tex]

Hence, the intensity of the light (in lumens) at a depth of 20 feet=11.45 lumens

is this answer correct? if not can somebody tell me what is the correct answer

Answers

Step-by-step explanation:

yes your answer is correct

Answer:

yes

Step-by-step explanation:

Suppose there are three balls in a box. On one of the balls is the number 1, on another is the number 2, and on the third is the number 3. You select two balls at random and without replacement from the box and note the two numbers observed. The sample space S consists of the three equally likely outcomes {(1, 2), (1, 3), (2, 3)} (disregarding order). Let X be the sum of the two balls selected. What is the mean of X

Answers

Step-by-step explanation:

a) X is a discrete uniform distribution. As the number of outcomes is only 3.

b) sum is at least 4

X ≥ 4--------

i.e  (1,3) or (2,3)

probability of X ≥ 4 is 2/3

2/3= 0.667

66.7 % is the probability of the outcome to have  a sum at least 4.

c) The 3 likely outcome of X

(1,2) where X ; 1+2=3

(1,3) where X ; 1+3=4

(2,3) where X ;  2+3=5

Mean = 3+4+5/ 3

Mean = 4

Feel free to ask any uncleared step

Which expression is equal to 52√13√?

26√13

65√2

526√13

526√13√

Answers

Answer:

26√13

Step-by-step explanation:

To make a committee 4 men are chosen out of 6 candidates. What is the probability that 2 certain people will serve on that committee

Answers

Answer:

The probability that 2 certain people will serve on that committee is 11.11%.

Step-by-step explanation:

Since to make a committee 4 men are chosen out of 6 candidates, to determine what is the probability that 2 certain people will serve on that committee the following calculation must be performed:

4/6 = 2/3

1/3 x 1/3 = X

0.333 x 0.333 = X

0.1111 = X

Therefore, the probability that 2 certain people will serve on that committee is 11.11%.

Answer:

[tex]\frac{2}{5}[/tex]

Step-by-step explanation:

6 groups, and 4 certain people

6

   C

        4

[tex]\frac{6!}{(6-2)!(2!)}[/tex]

1 × 2 × 3 × 4 × 5 × 6/1 × 2 × 3 × 4 × 1 × 2

1 × 2 × 3 × 4 × 5 × 6/1 × 2 × 3 × 4 × 1 × 2

5 × 6/ 1 × 2

30/2 = 15

15 possible combinations

4 people, and 2 specific ones

4

   C

        2

[tex]\frac{4!}{(4-2)!(2!)}[/tex]

1 × 2 × 3 × 4/1 × 2 × 1 × 2

1 × 2 × 3 × 4/1 × 2 × 1 × 2

12/2 = 6

[tex]\frac{6}{15}=\frac{\frac{6}{3} }{\frac{15}{3} } =\frac{2}{5}[/tex]

18. Which of the following is true for a circle that has a circumference of approximately 75 feet?
O The diameter is approximately 12 feet.
O The radius is approximately 12 feet.
O The radius is approximately 12 square feet.
O The diameter is approximately 12 square feet.

Answers

Answer:

A) The diameter is approximately 12 feet.

Step-by-step explanation:

C= piD

sq ft would be wrong bc this is not talking ab area

The mode of 3 numbers is 6 and the
range is 4. Write down a possible set of
numbers.​

Answers

Answer:

solution,

mode of 3 numbers is 6

range is 4

possible set of numbers are

{3,4,6,{} }

In June, an investor purchased 300 shares of Oracle (an information technology company) stock at $53 per share. In August, she purchased an additional 400 shares at $42 per share. In November, she purchased an additional 400 shares at $45. What is the weighted mean price per share? (Round your answer to 2 decimal places.)

Answers

Answer: The mean price per share is $22.91

The required weighted mean price per share is $46.09.

Given that,
In June, an investor purchased 300 shares of Oracle (an information technology company) stock at $53 per share. In August, she purchased an additional 400 shares at $42 per share. In November, she purchased an additional 400 shares at $45.
To determine the weighted mean price per share.

What is average?

The average of the values is the ratio of the total sum of values to the number of values.

What is mean?

The mean of the values is the ratio of the total sum of values to the number of values.

Here,
Required  weight mean = 300 * 53 + 400*42 + 400 * 42 / [300 + 400 + 400]
Required  weight mean = 50700/ [1100]
Required  weight mean = $46.09 per share.

Thus, the required weighted mean price per share is $46.09.

Learn more about mean here:

https://brainly.com/question/15397049

#SPJ2



I need help solving a problem, can u help me ?

Answers

Its 5
A^2+b^2=c^2
12^2 +b^2= 13^2
144+b^2 =169
169-144=25
square root 25 is 5

Which point is a solution to y equal greater than or less too
4x + 5?​

Answers

Answer:

4x+ 4

Step-by-step explanation:

Weights measured in grams of randomly selected M&M plain candies:

0.957 0.912 0.925 0.886 0.920 0.958 0.915 0.914 0.947 0.939 0.842

What is the range of weights of the middle 99.7% of M&M’s?

(round to the ten thousandths place)

Answers

Answer:

The range of weights of the middle 99.7% of M&M’s is between 0.8187 and 1.0203.

Step-by-step explanation:

The Empirical Rule states that, for a normally distributed random variable:

Approximately 68% of the measures are within 1 standard deviation of the mean.

Approximately 95% of the measures are within 2 standard deviations of the mean.

Approximately 99.7% of the measures are within 3 standard deviations of the mean.

Sample mean:

[tex]\overline{x} = \frac{0.957 + 0.912 + 0.925 + 0.886 + 0.920 + 0.958 + 0.915 + 0.914 + 0.947 + 0.939 + 0.842}{11} =  0.9195[/tex]

Sample standard deviation:

[tex]s = \sqrt{\frac{(0.957-0.9195)^2 + (0.912-0.9195)^2 + (0.925-0.9195)^2 + (0.886-0.9195)^2 + ...}{10}} = 0.0336[/tex]

What is the range of weights of the middle 99.7% of M&M’s?

By the Empirical Rule, within 3 standard deviations of the mean, so:

0.9195 - 3*0.0336 = 0.8187.

0.9195 + 3*0.0336 = 1.0203.

The range of weights of the middle 99.7% of M&M’s is between 0.8187 and 1.0203.

Which of the following displays cannot be used to compare data from two different sets?

Answers

Answer:

Scatter plot charts are good for relationships and distributions, but pie charts should be used only for simple compositions — never for comparisons or distributions.

Joanna set a goal to drink more water daily. The number of ounces of water she drank each of the last seven days is shown below.

60, 58, 64, 64, 68, 50, 57

On the eighth day, she drinks 82 ounces of water. Select all the true statements about the effect of the eighth day's amount on Joanna's daily amount distribution.
PLZ HELP ME I NEED AN ANSWER ASAP WILL NAME BRAINLIEST

Answers

(a) Data with the eight day's measurement.

Raw data:      [60,58,64,64,68,50,57,82],  

Sorted data:  [50,57,58,60,64,64,68,82]

Sample size = 8 (even)

mean            = 62.875

median         = (60+64)/2 = 62

1st quartile   = (57+58)/2 = 57.5

3rd quartile  = (64+68)/2 =  66

IQR = 66 - 57.5 = 8.5

(b) Data without the eight day's measurement.

Raw data:      [60,58,64,64,68,50,57]

Sorted data:  [50,57,58,60,64,64,68]

Sample size = 7 (odd)

mean            = 60.143

median         = 60

1st quartile   = 57

3rd quartile = 64

IQR = 64 -57 = 7

Answers:

1. The average is the same with or without the 8th day's data.  FALSE

2. The median is the same with or without the 8th day's data.  FALSE

3. The IQR decreases when the 8th day is included.                  FALSE

4. The IQR increases when the 8th day is included.                   TRUE

5. The median is higher when the 8th day is included.              TRUE

Answer:

The Interquartile range increases when the 8th day is included.          

The median is higher when the 8th day is included.

Step-by-step explanation:

i got it right. Hope this helps.

Other Questions
Goldilocks and the Three Bears What kind of writing style is used in this story? Which of the following statements about short-term goals is false? a. An example of a short-term goal would be buy a house in 2 years. b. You can work on a short-term goal immediately. c. Short-term goals can be accomplished quickly. d. Your short-term goals should be specific. Please select the best answer from the choices provided A B C D Given the range (1, 1), (4, 2), (2, -1), with a coordinate transformation of f(x, y) = (x-3, y+2), what is the domain?A. (4, -1), (7, 0), (5, -3)B. (-2, 3), (1, 4), (-1, 1)C. (1, 1), (2, 4), (2, -1)D. (3, 2), (12, 4), (-12, 2) PLEASE HELP ASAP!Select the reason that best supports statement 5 in the given proof.A. GivenB. Distributive Property C. SubstitutionD. Transitive Property On Tuesday at noon there were 4 inches of snow onthe ground. Then it snowed at a rate of i Inches perhour for 7 hours. By Tuesday at 7:00pm there were25 inches of snow on the ground. Which equationrepresents the situation? How many pounds of water must be evaporated from 50 pounds of a 3% salt solution so that the the remaining solution will be 5 % salt Find the remainder when f(x)=2x3+2x23x3 is divided by x2. what protects the cells of plants Blood pressure of 132/78. What does the 78 indicate? A) Pressure when the left ventricle contractsB) Overall blood pressure readingC) The difference between Volume and PulseD) The pressure when the left ventricle relaxes A stock analyst collected the following information about ABC Inc.: - The firm required rate of return on equity is 17% and its WACC is estimated at 14%. - Based a thorough forecast, the analyst estimates for the free cash flows to the firm for the next two years are 820,000 and 970,000 respectively. His estimates for the free cash flows to equity are however: 550,000 and 660,000 for the next two years respectively. - Both FCFFs and FCFEs are expected to grow at a constant rate of 5% after the second year. The value of equity is closest to: A model of the Pythagorean Theorem is shown below.If a = 6 and c = 10 , which of the following could NOT be used to find the value of b?A. 102 = 62 + b2B. 102 + 62 = b2,C. 100 = 36 + b2,D. 10036=b2 Find question attached. What is the probability of the parents having a daughter? solve for "c". a(b-c)=d Vent, Inc. reported net income of $770,000 for 20X1. Vent sold 15,000 shares of treasury stock acquired in a previous year on July 1 and 15,000 new shares on November 1. At year-end, 180,000 shares were outstanding. Vent had 20,000 shares of $100 par value 7% preferred stock outstanding all year. Vent paid dividends to the preferred shareholders. 1. The weighted average number of common shares used to compute earnings per share for 20X1 is:_____.2. Calculate the basic earnings per share for 2015.3. If each share of preferred stock is convertible into 2 shares of common stock, what is the diluted earnings per share for 2015? Can anyone explain me? cons of a mixed market economy The population of a town is 24,000 and isincreasing at a rate of 6% per year for 3 years Which digit is in the thousandths place?98.327A. 7B. 2C. 3D. 9 faa uma Crnica humorsticaA modalidade exigida a crnica humorstica, que lana mo da ironia e do humor como forma de criticar aspectos da sociedade, poltica, cultura ou economia, garantindo uma leitura envolvente e a reflexo acerca dessas questes. Tipo textual: narrativo pfv me ajudem!