11.1.21 A survey​ asked, "How many tattoos do you currently have on your​ body?" Of the males​ surveyed, responded that they had at least one tattoo. Of the females​ surveyed, responded that they had at least one tattoo. Construct a ​% confidence interval to judge whether the proportion of males that have at least one tattoo differs significantly from the proportion of females that have at least one tattoo. Interpret the interval. Let represent the proportion of males with tattoos and represent the proportion of females with tattoos. Find the ​% confidence interval for . The lower bound is nothing. The upper bound is nothing. ​(Round to three decimal places as​ needed.)

Answers

Answer 1

Complete question :

The Harris Poll conducted a survey in which they asked, "How many tattoos do you currently have on your body?" Of the 1205 males surveyed, 181 responded that they had at least one tattoo. Of the 1097 females surveyed, 143 responded that they had at least one tattoo. Construct a 95% confidence interval to judge whether the proportion of males that have at least one tattoo differs significantly from the proportion of females that have at least one tattoo. Interpret the interval.

Answer:

(−0.0085 ; 0.0481)

Step-by-step explanation:

Given that :

n1 = 1205 ; x1 = 181 ; n2 = 1097 ; x2 = 143 ; α = 95%

Zα/2 = 1.96 ( Z table)

Confidence interval : (p1 - p2) ± E

E =Zα/2 * √[(p1q1/n1) + (p2q2/n2)]

p1 = x1 /n1 =181/1205 = 0.1502

q1 = 1 - p1 = 1 -0.1502 = 0.8498

p2 = x2/n2 = 143/1097 = 0.1304

q2 = 1 - p2 = 1 -0.1304 = 0.8696

E = 1.96 * √(0.0001059 + 0.0001033)

E = 0.0283

p1 - p2 = 0.1502 - 0.1304 = 0.0198

Lower boundary = 0.0198 - 0.0283 = −0.0085

Upper boundary = 0.0198 + 0.0283 = 0.0481

(−0.0085 ; 0.0481)


Related Questions

Kitchen countertops can be
measured in millimeters.
How long is 1.50 m in mm?

Answers

Answer:

1500mm

Step-by-step explanation:

Multiply the length by 1000

therefore, 1.5×1000


The total cost of attending the movies, y, is directly proportional
with the number of tickets purchased, x. If it costs a family of four
$38.00 to attend the movies, what is the slope of this
relationship?

Answers

Answer:

The slope should be 34.00.

Step-by-step explanation:

What is the answer to this problem?

Answers

Answer:

Surface area = 24in

Step-by-step explanation:

I think its 6in x 4in

so like since the green cylinder is 6in i think you multiply it with the purple (sorry if I’m wrong)

At the beginning of the school year, Jamie had $500 in her savings account. She wants to have at least $200 left in the account at the end of the school year. Each week, she withdraws $30 for spending money. To determine how many weeks she can spend $30, Jamie wrote and solved this inequality.

500 − 30x ≥ 200
−500 −500
−30x ≥ −300
x ≥ 10
Review Jamie’s work. What was her error?

Answers

Her error was that she misplaced the numbers

-30x ≥ -300

its supose

to be -30x ≥ 200

Answer:

Jamie should have reversed the inequality when using the division property of inequality.

Step-by-step explanation:

Ms. Clark is building a patio that is 4 yards long and 3 yards wide. She has enough bricks to cover an area of 14 square yards. Does Ms. Clark have enough bricks to build the patio? Explain.​

Answers

Answer:

DONT CLICK THE LINK!!!! IT IS A BOT. THEY WILL. HACK.

Step-by-step explanation:

Given, we know that she has 14 bricks.

We also know that the patio is 4 yards long and 3 yards wide. If we multiply those two numbers together we get 12.

So, if we do the math 14-12=2 bricks left over.

Therefore, she will have enough bricks to build the patio.

app 19.study
Tools
Tools
Probability
Jacob performed an experiment with a weighted die, numbered 1 to 6. He rolled the die 125 times and recorded the results.
Complete the table below.
0.232
37
24
0.176
18
0.048
0.104
22
Result of Roll
Frequency
Experimental
Probability
1
2
13
3
0.144
4
29
5
0.296
6
Reset
Submit

Answers

Answer:

[tex]1 \to 22 \to 0.176[/tex]

[tex]2 \to 13 \to 0.104[/tex]

[tex]3 \to 18 \to 0.144[/tex]

[tex]4 \to 29 \to 0.232[/tex]

[tex]5 \to 37 \to 0.296[/tex]

[tex]6 \to 6 \to 0.048[/tex]

Step-by-step explanation:

Given

[tex]n = 125[/tex]

See attachment for proper table

Required

Complete the table

Experimental probability is calculated as:

[tex]Pr = \frac{Frequency}{n}[/tex]

We use the above formula when the frequency is known.

For result of roll 2, 4 and 6

The frequencies are 13, 29 and 6, respectively

So, we have:

[tex]Pr(2) = \frac{13}{125} = 0.104[/tex]

[tex]Pr(4) = \frac{29}{125} = 0.232[/tex]

[tex]Pr(6) = \frac{6}{125} = 0.048[/tex]

When the frequency is to be calculated, we use:

[tex]Pr = \frac{Frequency}{n}[/tex]

[tex]Frequency = n * Pr[/tex]

For result of roll 3 and 5

The probabilities are 0.144 and 0.296, respectively

So, we have:

[tex]Frequency(3) = 125 * 0.144 = 18[/tex]

[tex]Frequency(5) = 125 * 0.296 = 37[/tex]

For roll of 1 where the frequency and the probability are not known, we use:

[tex]Total \ Frequency = 125[/tex]

So:

Frequency(1) added to others must equal 125

This gives:

[tex]Frequency(1) + 13 + 18 + 29 + 37 + 6 = 125[/tex]

[tex]Frequency(1) + 103 = 125[/tex]

Collect like terms

[tex]Frequency(1) =- 103 + 125[/tex]

[tex]Frequency(1) =22[/tex]

The probability is then calculated as:

[tex]Pr(1) = \frac{22}{125}[/tex]

[tex]Pr(1) = 0.176[/tex]

So, the complete table is:

[tex]1 \to 22 \to 0.176[/tex]

[tex]2 \to 13 \to 0.104[/tex]

[tex]3 \to 18 \to 0.144[/tex]

[tex]4 \to 29 \to 0.232[/tex]

[tex]5 \to 37 \to 0.296[/tex]

[tex]6 \to 6 \to 0.048[/tex]

does the graph of this equation widen or narrow from the parent function? g(x)=3/4(x-5)^2+12

Answers

9514 1404 393

Answer:

  widen

Step-by-step explanation:

The vertical scale factor is 3/4, so the vertical extent is shortened at a given x-value distance from the axis of symmetry. That will give the appearance of making the parabola (slightly) wider.

Answer:

Widen is the answer.

Step-by-step explanation:

#CarryOnLearning

I've been asking since yesterday :(

Candace is designing a rectangular garden. The garden's diagonal must be 37.7 feet, and the ratio between the garden's base and height must be 12:5. Find the length of the garden's base and height. The garden's base is feet and its height is​

Answers

Answer:

Step-by-step explanation:

let the base=12x

and height=5x

(12x)²+(5x)²=37.7²

144x²+25x²=37.7²

169x²=37.7²

(13x)²=37.7²

13x=37.7

x=37.7/13=2.9

base=12×2.9=34.8 ft

height=5×2.9=14.5 ft

For which value of k does Limit as x approaches kf(x) = 4?

0
2
6
8

Answers

Answer:

2

Step-by-step explanation:

on Edge

Answer: 2

Step-by-step explanation:

have a great day!

What is the surface area of the right prism below? A 432 sq units B. 448 sq units C. 480 sq units D. 400 sq units​

Answers

[tex]\huge{\textbf{\textsf{{\color{pink}{An}}{\red{sw}}{\orange{er}} {\color{yellow}{:}}}}}[/tex]

D. 400 sq units

ThanksHope it helps

The surface area of the right prism given below is 432 square units.

What is Surface Area?

The area of a three dimensional object on it's outer surface is called the surface area of the object.

Given a right prism.

The right prism consists of three rectangular faces and two triangular faces.

Area of a triangular face = 1/2 × 8 × 6 = 24

Area of two triangular faces = 2 × 24 = 48 square units

Area of rectangular faces = (10 × 16) + (8 × 16) + (6 × 16)

                                          = 384 square units

Total area of the prism = 48 square units + 384 square units

                                      = 432 square units

Hence the total area of the prism is 432 square units.

Learn more about Surface Area here :

https://brainly.com/question/29298005

#SPJ7

As reported in Trends in Television, the proportion of US households who have at least one VCR is 0.592. If 8 households are selected at random, without replacement, from all US households, what is the (approximate) probability that the number having at least one VCR is exactly 4. Be sure to use many decimal places in your calculations (at least 4), but report your answer to three decimal places.

Answers

Answer:

0.23825

Step-by-step explanation:

Given :

p = 0.592 ; number of trials, n = 8

x = 4 ; q = 1 - p = 1 - 0.592 = 0.408

Using the binomial probability relation :

P(x = x) = nCx * p^x * q^(n-x)

P(x = 4) = 8C4 * 0.592^4 * 0.408^4

P(x = 4) = 70 * 0.592^4 * 0.408^4

P(x = 4) = 0.23825

What is the answer to this

Answers

Answer:

5 f

Re-order terms so that constants are on the left

. 5

5 f

solution

5 f

Irene purchased some earrings that regularly cost $55 for a friend's birthday. Irene used a "20% Off"
coupon.
How much did Irene pay for the earrings?

Answers

Answer:

44 dollars without tax so the earrings were 11 dollars off

44 dollar with 11 dollars off

Show your full solution

1. How much larger is the pizza in a circular pan with a 14-inch diameter than a pizza made in square pan with sides measuring 14 inches?

2. A photograph measuring 10 cm by 4 cm is mounted on a rectangular cardboard, to leaving a margin of 3 cm all around. What is the area of a photograph?​

Answers

Answer:

1.the square pan is larger by 12 inches

40 cm^2

Step-by-step explanation:

The difference in size can be determined by calculating the difference between the perimeter of the square pan and the circumference of a circle

perimeter of a square = 4 x length

14 x 4 = 56 inches

Circumference of a circle = πD = (22/7) x 14 = 44 inches

Difference in size = 56 - 44 = 12 inches

Area of a rectangle = length x width

10 x 4 - 40 cm^2

Find the median of the dot plot below 5 6 7 8 9 10 11 12 13​

Answers

Answer:

The median is 9

Step-by-step explanation:

Answer:

Hey love! Answer: 9

Step-by-step explanation:

these are the numbers 5 6 7 8 (9) 10 11 12 13

the median is simply just the one in the middle so this one is 9 because it has 4 numbers in front and 4 numbers after

Hope this helps!

which equation represents a line that passes through (5,4) with a slope of 2/5

Answers

Answer:

y = 2/5x +2

Step-by-step explanation:

y - 4 = 2/5(x -5)

y-4 = 2/5x -2

y = 2/5x +2

1.A woman is flying a kite. If she has 80 feet of string out and the kite is 55 feet up in the air,
what is the kite's angle of inclination?

Answers

Answer:

25 feet

Step-by-step explanation:

The waiting time W for accessing one record from a computer database is a random variable uniformly distributed between 0 and 28 milliseconds. The read time R for moving the information from the disk to the main memory is 7 milliseconds. The random variable X milliseconds is the total access time (waiting time + read time) to get one block of information from the disk. Before performing a certain task, the computer must access 6 different blocks of information from the disk. (Access times for different blocks are independent of one another.). Compute the followings:

a. E[X]
b. Vae[X]
c. E[A]

Answers

Solution :

Let

Waiting time for accessing one record = W

Read time for moving the information = R

Total time for accessing to get one block of information = X

So, the random variable X is defined as :

X = W + R

  = W + 7

a). Calculating E(X)

E(X) = E(W+7)

      = E(W) + 7

      [tex]$=\int_{0}^{28}\frac{1}{28-0}w dw +7$[/tex]

       [tex]$=\frac{1}{28}\int_{0}^{28}w dw +7$[/tex]

       [tex]$=\frac{1}{28}\left[\frac{w^2}{2}\right]_0^{28}+7$[/tex]

      [tex]$=\frac{1}{56}\left[28^2\right]+7$[/tex]

      [tex]$=\frac{28}{2}+7$[/tex]

     = 14 + 7

     = 21

b). Calculating Var(X)

V(X) = V(W+7)

      = V(W)+0

      = V(W)

     = [tex]$E(W^2)-[E(W)]^2$[/tex]

     [tex]$=\int_0^{28}\frac{1}{28}w^2 dw-[14]^2$[/tex]

    [tex]$=\frac{1}{28}\left[\frac{w^3}{3}\right]_0^{28}-196$[/tex]

   [tex]$=\frac{1}{28\times 3}\times 28^3-196$[/tex]

  [tex]$=\frac{28\times 28}{3}-196$[/tex]

 = 65.33

c). Considering A is the random variable that can be defined as follows:

A = 6(W+7)

   =6W + 42

So calculating E(A)

E(A) = E(6W + 42)

      = E(6W) +42

      = 6E(W) + 42

     = 6(14) + 42

     = 84 + 42

     = 126

The number of hours per week that the TV is turned on is determined for each family in a sample.
The mean of the data is 37 hours.
The median is 33.2 hours.
Twenty four of the families in the sample watched TV for less than 22 hrs per week.
The 16th percentile is 22hrs.
150 families participated in the study.
The first percentile is greater than or equal to 22 hours: True or False?

Answers

Answer:

False, the first percentile is less than 22 hours.

Step-by-step explanation:

xth percentile:

If a measure is said to be in the xth percentile, it means that x% of the measures are smaller than it, and (100-x)% are larger.

Twenty four of the families in the sample watched TV for less than 22 hrs per week. In the sample, there are 150 families.

This means that 22 is the:

24*100%/150 = 16th percentile.

The first percentile is greater than or equal to 22 hours: True or False?

The first percentile is less than the 16th percentile, which is 22. This means that this is false, the first percentile is less than 22 hours.

Which choice is the slope-intercept equation of the line shown below?
(1,2)

(0, -1)

A. y = 3x - 1
B. y = 2x-1
C. y = 2x + 1
D. y = 3x

Answers

Answer:

C is my answer

Step-by-step explanation:

Tori's Burgers cooks its burgers either well done or medium. Last night the restaurant served
25 burgers in all, 5 of which were well done. What percentage of the burgers were well done?
Write your answer using a percent sign (%).

Answers

Answer: 20%
5/25 = .2
.2 x 100 = 20%

Help me please ( on the image )

Answers

Answer:

[tex]\frac{\pi}{3}[/tex] radians

Step-by-step explanation:

Number of hours on a clock = 12

Since, measure of a circle at the center = 360°

Measure of central angle formed by the arc between each number (representing hours) = [tex]\frac{360}{12}[/tex]

                                  = 30°

Central angle formed by the arc intercepted by the hands of the clock at 8:00 = 4 × 30°

        = 120°

Therefore, angle measure in radians = [tex]\frac{\pi }{360}\times (120^0)[/tex]

                                                              = [tex]\frac{\pi }{3}[/tex]

Angle formed by the hands of the clock at 8:00 = [tex]\frac{\pi}{3}[/tex] radians

Explain how you found your answer

Answers

Answer:

29°

Step-by-step explanation:

151° + a=180°

We know the sum of angles in a straight line is 180°

a= 180°-151°

The sign changed as it changed sides

a= 29°

You have been given the task of designing a study concerning the lifetimes of five different types of electric motor. The initial question to be addressed is whether there are differences in mean lifetime among the five types. There are 20 motors, four of each type, available for testing. A maximum of five motors can be tested in a day. The ambient temperature differs from day to day, and this can affect motor lifetime.
a. Describe how you would choose the five motors to test each day. Would you use a completely randomized design? Would you use any randomization at all?
b. If X;j represents the measured lifetime of a motor of type i tested on day j, express the test statistic for testing the null hypothesis of equal lifetimes in terms of the Xir

Answers

Answer:

a-As the only factor of interest is type of electric motor, thus instead of using 1-factor randomization, a randomized block design is used where at maximum one motor of each type is tested every day.

b- The test statistic is given as

[tex]F_{I-1,(I-1)(J-1)}=\dfrac{12\left(\Sigma^{5}_{i=1}\bar{X}^{2}_{i.}-IJ\bar{X}^2_{..}\right) }{\Sigma^5_{i=1}\Sigma^4_{j=1}\left(X_{ij}-\bar{X}_{i.}-\bar{X}_{.j}+\bar{X}_{..}\right)^2}[/tex]

Step-by-step explanation:

a-

This is done such that the days are considered as blocks and the randomization is only occuring within the block. The order of testing is random. However the condition is implemented such that one motor of each type is tested each day.

b-

The F-Value is given as

[tex]F-Value=\dfrac{MSA}{MSAB}[/tex]

Here MSA is given as

[tex]MSA=\dfrac{J\Sigma^I_{i=1}(\bar{X}_{i.}-\bar{X}_{..})^2}{I-1}[/tex]

Here

I is the number of types which is 5J is the number of motors of each type which is 4[tex]\bar{X}_{i.}[/tex] is the row-wise mean which is given as [tex]\bar{X}_{i.}=\dfrac{1}{J}\Sigma^J_{j=1}X_{ij}[/tex][tex]\bar{X}_{..}[/tex] is the sample grand mean which is given as [tex]\bar{X}_{..}=\dfrac{1}{IJ}\Sigma^I_{i=1}\Sigma^J_{j=1}X_{ij}[/tex]

Similarly MSAB is given as

[tex]MSAB=\dfrac{\Sigma^I_{i=1}\Sigma^J_{j=1}\left(X_{ij}-\bar{X}_{i.}-\bar{X}_{.j}+\bar{X}_{..}\right)^2}{(I-1)(J-1)}[/tex]

Here

I is the number of types which is 5J is the number of motors of each type which is 4[tex]\bar{X}_{i.}[/tex] is the row-wise mean which is given as [tex]\bar{X}_{i.}=\dfrac{1}{J}\Sigma^J_{j=1}X_{ij}[/tex][tex]\bar{X}_{..}[/tex] is the sample grand mean which is given as [tex]\bar{X}_{..}=\dfrac{1}{IJ}\Sigma^I_{i=1}\Sigma^J_{j=1}X_{ij}[/tex][tex]\bar{X}_{.j}[/tex] is the column-wise mean which is given as [tex]\bar{X}_{.j}=\dfrac{1}{I}\Sigma^I_{i=1}X_{ij}[/tex][tex]X_{ij}[/tex] is the any motor j of type i

By putting these values and simplifying, equation becomes:

[tex]F-Value=\dfrac{MSA}{MSAB}\\\\F-Value=\dfrac{\dfrac{J\Sigma^I_{i=1}(\bar{X}_{i.}-\bar{X}_{..})^2}{I-1}}{\dfrac{\Sigma^I_{i=1}\Sigma^J_{j=1}\left(X_{ij}-\bar{X}_{i.}-\bar{X}_{.j}+\bar{X}_{..}\right)^2}{(I-1)(J-1)}}\\\\F-Value=\dfrac{\dfrac{4\Sigma^5_{i=1}(\bar{X}_{i.}-\bar{X}_{..})^2}{5-1}}{\dfrac{\Sigma^5_{i=1}\Sigma^4_{j=1}\left(X_{ij}-\bar{X}_{i.}-\bar{X}_{.j}+\bar{X}_{..}\right)^2}{(5-1)(4-1)}}\\\\[/tex]

This is further simplified as

[tex]F-Value=\dfrac{\dfrac{4\Sigma^5_{i=1}(\bar{X}_{i.}-\bar{X}_{..})^2}{4}}{\dfrac{\Sigma^5_{i=1}\Sigma^4_{j=1}\left(X_{ij}-\bar{X}_{i.}-\bar{X}_{.j}+\bar{X}_{..}\right)^2}{12}}\\\\F-Value=\dfrac{\Sigma^5_{i=1}(\bar{X}_{i.}-\bar{X}_{..})^2}{\dfrac{\Sigma^5_{i=1}\Sigma^4_{j=1}\left(X_{ij}-\bar{X}_{i.}-\bar{X}_{.j}+\bar{X}_{..}\right)^2}{12}}\\\\[/tex]

The numerator can be written as

[tex]F-Value=\dfrac{\Sigma^{5}_{i=1}\bar{X}^{2}_{i.}-IJ\bar{X}^2_{..}}{\dfrac{\Sigma^5_{i=1}\Sigma^4_{j=1}\left(X_{ij}-\bar{X}_{i.}-\bar{X}_{.j}+\bar{X}_{..}\right)^2}{12}}\\\\F-Value=\dfrac{12(\Sigma^{5}_{i=1}\bar{X}^{2}_{i.}-IJ\bar{X}^2_{..})}{{\Sigma^5_{i=1}\Sigma^4_{j=1}\left(X_{ij}-\bar{X}_{i.}-\bar{X}_{.j}+\bar{X}_{..}\right)^2}}\\[/tex]

if f(x)= 3x+16 what is f(2)

Answers

Answer:

22

Step-by-step explanation:

Answer: 3(2)+16=22

Reason:
3x2=6
6+16=22
So the answer is 22

Dan bought 20 bunches of seedless green grapes for $48. How many bunches can Kali buy if she has $12?

5

29

4

6​

Answers

Answer:

48/20=2.4

12/2.4=5

Step-by-step explanation:

Kai can buy 5 bunches of grapes if she has $12.

Answer:

It's 29.

Step-by-step explanation:

48/20=2.4

12x2.4=28.8

Round up to 29.

Please help me with this real quick

Answers

Answer: 7.5 miles

Step-by-step explanation:

think of it as a triangle; the bold line is the hypotenuse, or x.

 8   |\   x

      |_\              it's not a good triangle but you get the point

       6

and then get out pythagorean theorem: a^2+b^2=c^2

put the numbers in: 8^2 + 6^2 = x^2

do some math:

64+36=x^2

100=x^2 (and then find square root)

10=x

BUT, it said each unit was 3/4 of a mile, so we must multiply 10 by 3/4 to get the actual distance, which is 7.5

PLEASE HELP PLEASE (dont do links)

Answers

Answer:

B

-2(0)²+24(0)-54

= -54

Answer:

I think its C

Step-by-step explanation:

y intercepts (0,-54)

An aquarium owns 5 identical tanks. All together, the tanks can hold 86 gallons of water. How much water can each tank hold?
All tanks together =

Answers

Answer:  17.2 for each tank

Helppppppppppppppppppppp

Answers

D) No, because the y-intercepts are different

Mark with crown please!
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Preparing Questions for an InterviewIn this task, you will research and prepare questions for an interview with three experts in a panel discussion. The panel will discuss the following topics:body imagehormonal and chemical changes in teensscreen time usage for adolescentsi mainly need two questions to the third one "screen time usage for adolescents" but if you wanna answer the first two also then im all for it.create 2 questions for each topic please does this look good it's for my art class it's Jordan sauste PLEASE ANSWER ASAP WILL GIVE POINTS!!!! You use the fixed manipulator to Group of answer choices round floating-point numbers that are displayed in fixed-point notation to the specified number of decimal places round floating-point numbers that are displayed in scientific notation to the specified number of significant digits format floating-point numbers in fixed-point notation all of the above a and b only Last Saturday, Emily and Lauren went to the ice cream shop. Enter an expression showing how much they spent together if Emily spent $4.53 and Lauren spent d dollars. Can yall help me with this pls its due rn and im cryinggggg ill definetly give brainliesttt : ( if y=5 x=9 find m and solve y=m+3x Which of the following is an acceptable method to directly measure volume using the metric system?A.Using a balance scale to measure pounds.B.Using a graduated cylinder to measure liters.C.Using a graduated cylinder to measure gallons.D.Using a balance scale to measure grams. what events in Hitler's life may have triggered his aggersion? how do engineers communicate their design ideas? necesito ejemplos de actitud filosfica por favor what is the formula of finding the value? woPoints A, B, C, and D are plotted on the number line.ABC Dtott-0.6 -0.4 -0.2-0.8Which point is plotted at -0.45?A Help plz asap asap plz 16. How would you tell someone who is older than you TO DO thefollowing: Hacer ejercicio *O Haga ejercicio!O Hagua ejercicio!O Haz ejercicio! 41. Consider the perimeter of the triangle shown. First, find the length of the hypotenuse. Need ASAP Ill mark brainliest if right what is friction and the types withe examples. Its voice was like a magnet, always callingher, and she longed to respond.What does the simile in this sentence mean? In order to compare the performance of students in large enrollment and small enrollment sections, 35 students from large sections and 35 students from small sections of a freshman mathematics course were randomly selected. The mean and sample standard deviation of grades on the common final exam for the students from large sections were 72.8 and 7.4; for the students from small sections, the mean and standard deviation were 75.3 and 6.8. A 90% confidence interval for the difference in the mean common final exam scores between students in the two types of sections is about: