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.

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.

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

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

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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).

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

(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.

Answer:

Option D

Step-by-step explanation:

correct answer on edge :)

Answer:

D <3

Step-by-step explanation:

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.

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]

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.

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.

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

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

Step-by-step explanation:

yes your answer is correct

Answer:

yes

Step-by-step explanation:

Answer:

I don't see any statements here.

Anyway, the answer is 8.

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

Answer:

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

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

Answer:

Line A

Step-by-step explanation:

graph it

Answer: Oh heaven nah

Step-by-step explanation: Lord have mercy

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

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

Answer:

26√13

Step-by-step explanation:

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

Answer:

solution,

mode of 3 numbers is 6

range is 4

possible set of numbers are

{3,4,6,{} }

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

Answer:

4x+ 4

Step-by-step explanation:

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

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.

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

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

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