30 randomly selected students took the statistics final. If the sample mean was 84, and the standard deviation was 12.2, construct a 99% confidence interval for the mean score of all students

Answers

Answer 1

The confidence interval for the mean score of the 30 randomly selected students is: 99% CI {78.26, 89.73}

What is confidence interval?

Confidence interval is the range of values for which which is expected to have the values at a certain percentage of the times.

How to construct a 99% confidence interval

Given data form the question

99% confidence interval

30 randomly selected students

mean sample = 84

Standard deviation = 12.2

Definition of variables

confidence level, CI = 99%

mean sample, X = 84

standard deviation, SD = 12.2

Z score, z = 2.576

from z table z score of 99%confidence interval = 2.576

sample size, n = 30

The formula for the confidence interval is given by

[tex]CI=X+Z\frac{SD}{\sqrt{n} }[/tex]    OR    [tex]CI=X-Z\frac{SD}{\sqrt{n} }[/tex]  

[tex]=84+2.576\frac{12.2}{\sqrt{30} }[/tex]

=[tex]=84+2.576*2.2274[/tex]

= 84 + 5.7378     OR       84 - 5.7378

= 89.7378           OR        78.2622

=  89.73 to 78.26  

The confidence interval for the mean score of all students is 78.26 to 89.78

Learn more about confidence interval at: https://brainly.com/question/17097944

#SPJ1


Related Questions

What is f(2) - f(0) answer choices:A) 1B) 2C) 3D) 4

Answers

Explanation

The points of the graph of a function f(x) have the form (x,f(x)). This means that the values of f(0) and f(2) are the y-values of the points in the graph that have 0 and 2 as their x-values. If you look at the graph you'll notice that the points (0,1) and (2,4) are part of the graph which implies that:

[tex]\begin{gathered} (0,f(0))=(0,1)\rightarrow f(0)=1 \\ (2,f(2))=(2,4)\rightarrow f(2)=4 \end{gathered}[/tex]

Then we get:

[tex]f(2)-f(0)=4-1=3[/tex]Answer

Then the answer is option C.

Joseph owns a 50 inch TV and it measures 50 inch on the diagonal. if the television is 40 inches across the bottom find the height of the TV

Answers

Let's draw the tv with the given values.

Note that we will form a right triangle with heigh of h, base of 40 and a hypotenuse of 50.

The Pythagorean Theorem is :

[tex]c^2=a^2+b^2[/tex]

where c is the hypotenuse, a and b are the legs of the triangle.

Using the formula above. we will have :

[tex]\begin{gathered} 50^2=40^2+h^2 \\ 2500=1600+h^2 \\ h^2=2500-1600 \\ h^2=900 \\ \sqrt[]{h^2}=\sqrt[]{900} \\ h=30 \end{gathered}[/tex]

The answer is 30 inches

4. Find the slope of the two points: (-3,-2) & (5, -8)
Enter Numerical value ONLY. NO Decimals

Try Again!
5. Find the slope of the two points: (6, 10) and (-2, 10) *
Enter Numerical value ONLY. NO Decimals
Your answer
This is a required question

Answers

Answer:

The slope of (-3, -2) and (5, -8) is -3/4

The slope of (6, 10) and (-2, 10 ) is 0

Step-by-step explanation:

[tex]\frac{-8 - (-2)}{5 - (-3)} = \frac{-6}{8} = -\frac{3}{4}[/tex]

and

[tex]\frac{10 - 10}{-2 - 6} = \frac{0}{-8} = 0[/tex]

How many degrees was ABCDE rotated? (submit your answer as a number)

Answers

If a figure has a vertex, (x, y) and it is rotated 180 degrees counterclockwise, the corresponding vertex of the new image would have a coordinate of (- x, - y)

Looking at the given figure, we would compare the corresponding coordinates of a given vertex. Looking at vertex A,

For the original figure, the coordinate is (1, 3)

For the ratated figure, the coordinate of A' is (- 1, - 3)

This corresponds to what was we stated earlier

Thus, it was rotated 180 degrees in the counterclockwise direction

Which of the following measurements form a right triangle? Select all that apply.

Answers

We are asked to find which of the measurements form a right triangle.

A right triangle is a triangle that has an angle of 90°, and also we can use the Pythagorean theorem in them.

The Pythagorean theorem tells us that the sum of the two legs of the triangle squared is equal to the hypotenuse squared:

[tex]a^2+b^2=c^2[/tex]

Where a and b are the legs of the triangle and c is the Hypotenuse. Also, in the right triangle, the hypotenuse is the longest side of the triangle.

We will use the Pythagorean theorem formula on all of the options using the first two given measures as a and b, and check that we the third measure as the value of c.

Option A. 7in, 24in, and 25 in.

We define:

[tex]\begin{gathered} a=7 \\ b=24 \end{gathered}[/tex]

And apply the Pythagorean theorem:

[tex]7^2+24^2=c^2[/tex]

And we solve for c. If the result for x is 25, the triangle will be a right triangle, if not, this will not be an answer.

-Solving for c:

[tex]\begin{gathered} 49+576=c^2 \\ 625=c^2 \end{gathered}[/tex]

Taking the square root of both sides we find c:

[tex]\begin{gathered} \sqrt[]{625}=c \\ 25=c \end{gathered}[/tex]

Since we get the third measure as the value of c option A is a right triangle.

Option B. 18ft, 23ft, and 29 ft.

we do the same as did with option A. First, define a and b:

[tex]\begin{gathered} a=18 \\ b=23 \end{gathered}[/tex]

Apply the Pythagorean theorem:

[tex]18^2+23^2=c^2[/tex]

And solve for c:

[tex]\begin{gathered} 324+529=c^2 \\ 853=c^2 \\ \sqrt[]{853}=c \\ 29.2=c \end{gathered}[/tex]

We get 29.2 instead of just 29, thus option B is NOT a right triangle.

Option C. 10in, 24in, and 26 in.

Define a and b:

[tex]\begin{gathered} a=10 \\ b=24 \end{gathered}[/tex]

Apply the Pythagorean theorem:

[tex]10^2+24^2=c^2[/tex]

Solve for c:

[tex]\begin{gathered} 100+576=c^2 \\ 676=c^2 \\ \sqrt[]{676}=c \\ 26=c \end{gathered}[/tex]

We get 26 which is the third measure given, thus, option C is a right triangle.

Option D. 10yd, 15yd, and 20yd.

Define a and b:

[tex]\begin{gathered} a=10 \\ b=15 \end{gathered}[/tex]

Apply the Pythagorean theorem:

[tex]\begin{gathered} 10^2+15^2=c^2 \\ 100+225=c^2 \\ 325=c^2 \\ \sqrt[]{325}=c \\ 18.03=c \end{gathered}[/tex]

We don't get 20yd as the value of c, thus, option D is NOT a right triangle.

Option E. 15mm, 18mm, and 24 mm

Define a and b:

[tex]\begin{gathered} a=15 \\ b=18 \end{gathered}[/tex]

Apply the Pythagorean theorem

[tex]\begin{gathered} 15^2+18^2=c^2 \\ 225+324=c^2 \\ 549=c^2 \\ \sqrt[]{549}=c \\ 23.43=c \end{gathered}[/tex]

We don't get 24 as the value of c, thus, option E is Not a right triangle.

Answer:

Option A and Option C are right triangles.

if angle 2 = 106 degrees, what is the measurement of angle 6 ? ( better explanation in picture )

Answers

angle 2 and angle 6 are corresponding angles.

Since the lines crossed by the trnasversal are parallel, corresponding angles are congruent. (equal)

angle 6 = 106°

Please provide deep explanation, so i can understand and learn. Thank you

Answers

Assume the height of the box is x.

5 reams of paper have 5 x 500 = 2500 sheets of paper.

This means that each sheet of paper has a thickness of x/2500.

Two sheets of paper have a thickness of 2 times x/2500.

Simplifying the fraction:

[tex]2\cdot\frac{x}{2500}=\frac{x}{1250}[/tex]

Two sheets of paper have a thickness of 1/1250th of the height of the box.

Assume the height is x = 20 cm, then two sheets are 20/1250 = 0.016 cm thick.

What is the volume of this sphere? Use a ~ 3.14 and round your answer to the nearest! hundredth. 5 m cubic meters

Answers

We will have the following:

[tex]V=\frac{4}{3}\pi r^3[/tex]

Now, we replace the values and solve:

[tex]V=\frac{4}{3}(3.14)(5)^3\Rightarrow V\approx523.33[/tex]

So, the volume of the sphere is approximately 523.33 cubic meters.

***Example with an 8 m radius***

If the radius of the sphere were of 8 meters, we would have:

[tex]V=\frac{4}{3}(3.14)(8)^3\Rightarrow V\approx2143.57[/tex]

So, the volume of such a sphere would be approximately 2143.57 cubic meters.

Mario constructs a scale model of a building with a rectangular base. His model is 4.2 inches in length and 2 inches in width. The scale of the model is 1 inch = 15 feet What is the actual area, in square feet, of the base of the building?

Answers

First let's use two rules of three to determine the actual dimensions of the building.

For the length, we have:

[tex]\begin{gathered} 1\text{ inch}\to15\text{ feet} \\ 4.2\text{ inches}\to x\text{ feet} \\ \\ \frac{1}{4.2}=\frac{15}{x} \\ x=15\cdot4.2=63 \end{gathered}[/tex]

For the width:

[tex]\begin{gathered} 1\text{ inch}\to15\text{ feet} \\ 2\text{ inches}\to x\text{ feet} \\ \\ \frac{1}{2}=\frac{15}{x} \\ x=15\cdot2=30 \end{gathered}[/tex]

Now, calculating the area of the building base, we have:

[tex]\text{Area}=63\cdot30=1890\text{ ft2}[/tex]

So the area of the building base is 1890 ft².

In solving for the inverse function for y = sqrt(3x + 2) - 1 , which of the following represents the first step?

Answers

we know that

The first step to find out the inverse of the function is to exchange the variables (x for y and y for x)

therefore

the answer is the second option

A machine that makes
toy spinners operates for 8 hours each
day. The machine makes 7,829 toy
spinners in
day. About how
many toy
spinners does the machine make each
hour?

Answers

Using the unitary method, the number of toy spinners the machines will make in an hour is 2069.

The unitary approach is a strategy for problem-solving that involves first determining the value of a single unit, then multiplying that value to determine the required value.

A machine makes 7829 toy spinners in a day.

The machines operate for 8 hours each day to make the toy spinners.

So,

8 hours = 7829

Then by using the unitary method the number of toy spinners the machines will make each hour will be:

8 hours = 7829

24 hours = x toy spinner

Toys in one hour = ( 7829/ 24 ) × 8

Toys in one hour = 326.20833 × 8

Toys in one hour = 2609.6667

Toys in one hour = 2069

Learn more about unitary method here:

brainly.com/question/22056199

#SPJ1

Based on the graph of f(x) shown here what is f^-1(8).

Answers

Answer

2

Explanation:

f⁻¹(8) is equal to the value of x that makes f(x) = 8. So, taking into account the graph, we get:

Therefore, f⁻¹(8) = 2. So the answer is 2

h(r) = (r +1)(r+8)1) What are the zeros of the function?Write the smaller r first, and the larger second.smaller r =larger s 2) What is the vertex of the parabola

Answers

For the zeros of the function, we have to solve h(r)=0, therefore:

[tex]\begin{gathered} h(r)=(r+1)(r+8) \\ h(r)=0 \\ \Rightarrow(r+1)(r+8)=0 \\ \Rightarrow r=-1\text{ or } \\ r=-8 \end{gathered}[/tex]

then, the smaller r is -8 and the larger is -1.

Now, to find the vertex of the parabola, we can find the x-coordinate of the vertex from the general rule:

[tex]\begin{gathered} f(x)=ax^2+bx+c \\ \text{ x-coordinate: -b/2a} \end{gathered}[/tex]

In this case, we have the following:

[tex]\begin{gathered} h(r)=(r+1)(r+8)=r^2+8r+r+8=r^2+9r+8 \\ \Rightarrow a=1,b=9 \\ \Rightarrow-\frac{b}{2a}=-\frac{9}{2(1)}=-\frac{9}{2} \end{gathered}[/tex]

now that we have the x-coordinate of the vertex, we just evaluate the function on that point to find the y-coordinate of the vertex:

[tex]h(-\frac{9}{2})=(-\frac{9}{2}+1)(-\frac{9}{2}+8)=(-\frac{7}{2})(\frac{7}{2})=-\frac{49}{4}[/tex]

therefore, the vertex of the parabola is the point (-9/2,-49/4)

For each equation, choose the statement that describes its solution. If applicable, give the solution.

Answers

w=2

All real numbers are solutions

1) In this question, let's solve each equation, and then we can check whether there are solutions, which one would be.

2) Let's begin with the first one, top to bottom

[tex]\begin{gathered} 2(w-1)+4w=3(w-1)+7 \\ 2w-2+4w=3w-3+7 \\ 6w-2=3w+4 \\ 6w-3w=4+2 \\ 3w=6 \\ \frac{3w}{3}=\frac{6}{3} \\ w=2 \end{gathered}[/tex]

Note that we distributed the factors outside the parenthesis over the terms inside.

So for the first one, we can check w=2

3) Moving on to the 2nd equation, we can state:

[tex]\begin{gathered} 6(y+1)-10=4(y-1)+2y \\ 6y+6-10=4y-4+2y \\ 6y-4y-2y=4-4 \\ 6y-6y=0 \\ 0y=0 \end{gathered}[/tex]

So, there are infinite solutions for this equation, or All real numbers are solutions

0896. Calculate the atomic mass of copper if copper-63 is 69.17% abundant and copper-65 is30.83% abundant.

Answers

The atomic mass of the copper is

[tex]63\times69.17\text{ \% + 65}\times30.83\text{ \%}[/tex]

solve the above expression

[tex]63\times\frac{69.17}{100}+65\times\frac{30.83}{100}[/tex]

[tex]63\times\frac{6917}{10000}+65\times\frac{3083}{10000}[/tex][tex]46.35+20.03=66.38[/tex]

So the atomic weight of the mixture is 66.36 .

Hello! I need some help with this homework question, please? The question is posted in the image below. Q7

Answers

SOLUTION

Since -3 is a zero of the function then x=-3

This implies

x+3 is a factor of the polynomial

Following the same procedure, since 2 and 5 are zeros then

x-2 and x-5 are factors

Hence the polynomial can be written as

[tex]y=a(x+3)(x-2)(x-5)[/tex]

Since the graph passes through the point (7,300)

Substitute x=7 and y=300 into the equation

This gives

[tex]300=a(7+3)(7-2)(7-5)[/tex]

Solve the equation for a

[tex]\begin{gathered} 300=a(10)(5)(2) \\ 300=100a \\ a=\frac{300}{100} \\ a=3 \end{gathered}[/tex]

Substitute a into the equation of the polynomial

[tex]y=3(x+3)(x-2)(x-5)[/tex]

Therefore the answer is

[tex]y=3(x+3)(x-2)(x-5)[/tex]


L1 : y=−4x+3L2 : y=4x−1


Answers

Answer:

Assuming you're trying to find where the lines intersect (their solution), the point where they intersect is (1/2 , 1).

Step-by-step explanation:

When you are trying to find the point where two lines intersect, you have to find the x and y values of that point. To do that, just set the lines equal to each other.

First, since y must equal y:

y = y

-4x + 3 = 4x - 1

Now solve for x:

-8x + 3 = -4

-8x = -4

8x = 4

x = 1/2

We just found the x value of the shared point. Now we need to find the y value of that point. Again, since the two lines share this point, plugging in the x value will result in the same y value for both lines.

So just plug in x to any of the equations: (I think y=4x-1 is easier)

y(1/2) = 4(1/2) - 1     or      y = 4(1/2) - 1  (it doesn't matter how you write it)

y(1/2) = 2 - 1           or      y = 2 - 1

y(1/2) = 1

So the point is:

(1/2 , 1)

To check you can plug in the y value you find, 1 in this case, and solve for x. If you get the same x value as before, everything is correct.

So:

(1) = -4x + 3

-2 = -4x

1/2 = x    or    x = 1/2

Great! Everything is correct.

This may seem like a very long process, but it is very easy. Just find the x and y values that the lines share by setting the lines equal to each other.

if 1ml = 0.00011 then 9ml= _____

Answers

if 1ml = 0.00011 then 9ml=

Apply proportion

0.00011/1=x/9

solve for x

x=9*0.00011

x=0.00099

answer is

0.00099

Find the union of E and L.Find the intersection of E and L.Write your answers using set notation (in roster form).

Answers

For the intersection operation we have to look what elements both sets have in common, in this case both E and L has the number 8. Then the second answer is:

[tex]E\cap L=\lbrace8\rbrace[/tex]

Now, the union operation adds the all elements into a single set without repetition, in this case the first answer is:

[tex]E\cup L=\lbrace-2,1,2,3,6,7,8\rbrace[/tex]

−1= 8x+2i need help with this problem,

Answers

Given

-1 = 8x + 2

Answer

-1 = 8x + 2

-1 -2 =8x

-3 = 8x

x = -3/8

Please help me, i struggle with these types of problems

Answers

Solution

[tex]\begin{gathered} 11x-3=9x+15 \\ \\ 2x=18 \\ \\ x=9 \end{gathered}[/tex]

Therefore, we find m < 7

[tex]\begin{gathered} 11x-3 \\ \\ 11(9)-3 \\ \\ 99-3 \\ \\ 96\degree \end{gathered}[/tex]

D(-9,4) E(-3,4) F(-3,10) G(-9,10) rotation 180 clockwise

Answers

Answer:

D = (9,-4)        E = (3,-4)       F= (3, -10)         G=(9,-10)

Step-by-step explanation:

Simply switch the signs (- or +)

Ex: rotate (9,1) 180 degrees

Your answer would be (-9,-1)

A leaking pond loses 16 gallons of water in 47 hours. How many gallons of water will it lose in 33 hours?

Answers

A leaking pond loses 16 gallons of water in 47 hours.

How many gallons of water will it lose in 33 hours?

To solve this question we can use a rule of three:

16 gallons is to 47 hours as x gallons is to 33 hours:

[tex]\frac{16}{47}=\frac{x}{33}\Longrightarrow x=\frac{33\cdot16}{47}=\frac{528}{47}=\text{ 11.23}[/tex]

Answer:

11.23 gallons

(0,1), (2,4), (4,7) (9.1)}Domain:Range:

Answers

The domain of an ordered pair are its first elements and its range are all the second elements of the ordered pair.

So, the domain ={0,2,4,9}

Range={1,4,7,1}

A team won 5 and lost 2 of their first 7 games. The team continued to win at this rate and won w games in the 28-game season. Which of the following proportions could be used to determine w? 2. 7 28 B 2 5 28 5 7 28 D U NICT 28

Answers

Answer:

C. 5/7 = w/28

Explanation:

We're told from the question, the team won 5 and lost 2 of their first 7 games and later continued to win at this rate and won w games in the 28-game season.

Since w represents the number of games won in a 28-game season, in order to create a proportion to determine the value of w, we have to consider the number of games won (which was 5) in 1st 7 games.

So the proportion can then be written as;

[tex]\frac{5}{7}=\frac{w}{28}[/tex]

A cookie recipe calls for 3/4 of a cup of flour and makes 2dozen cookies. How many cookies can Julia make if she has 12cups of flour and wants to use it all

Answers

Given that 3/4 of a cup of flour is used to cook 2 dozen cookies,

[tex]\frac{3}{4}\text{ cup of flour}\equiv2\text{ dozen cookies}[/tex]

Consider the conversion,

[tex]1\text{ dozen}=12\text{ units}[/tex]

So it follows that,

[tex]\frac{3}{4}\text{ cup of flour}\equiv2\cdot12=24\text{ cookies}[/tex]

Multiply both sides by 4/3 as follows,

[tex]\begin{gathered} \frac{3}{4}\cdot\frac{4}{3}\text{ cups of flour}\equiv24\cdot\frac{4}{3}\text{ cookies} \\ 1\text{ cup of flour}\equiv32\text{ cookies} \end{gathered}[/tex]

So, 32 cookies can be cooked using 1 cup pf flour.

Given that Julia has 12 cups of flour, so the number of cookies that she can cook, is calculated as,

[tex]12\text{ cups of flour}\equiv32\cdot12=384\text{ cookies.}[/tex]

Thus, Julia can make 384 cookies if she uses 12 cups of flour.

Which region labeled in the graph below would represent the solution (the final shaded area) to the system of linear inequalities:≤12−3<−23+1

Answers

Since both inequalities include the less than symbol, <, the shaded region must be below the two lines.

The intersection (common) of the shaded regions, which are both below the two lines, is region D.

which fraction remains in the quotient when 4,028 is divided by 32

Answers

We get that

[tex]\frac{4028}{32}=\frac{1007}{8}=\frac{1000}{8}+\frac{7}{8}=125+\frac{7}{8}[/tex]

so the fractions that remains is 7/8

Could I please get help with finding the correct statements and reasonings. I think I messed up line number four because it keeps saying the line is incorrect and that I can not validate it l but

Answers

Answer:

Step-by-step explanation:

[tex]undefined[/tex]

translating words into algebraic symbols its not -70 or -7

Answers

translating words into algebraic symbols ​

a number x = x

decreased by seventy = -7

y= x-70

___________________

Answer

x-70

Other Questions
a communication system consists of n components, each of which will, independently, function with probability p. the total system will be able to operate effectively if at least one-half of its components function. (a) let x denote the number of functioning components out of the n components. what is the distribution of x? (b) what is the probability that a 5-component system will function? (c) for what values of p is a 5-component system more likely to operate effectively than a 3-component system? apart from suffering from recurrent and prolonged infections, marie curie also experienced the following signs and symptoms: fatigue, rapid heart rate, pale skin, easy bruising, prolonged bleeding from cuts, and dizziness. bone marrow transplant was not an option at that time and so blood transfusion was the treatment of choice.?trackid The purpose of ______ is to monitor performance and take corrective action as needed to ensure that objectives are met. Here is a system of equations.y=-3x+3y=-x-1Graph the system. Then write its solution. Note that you can also answer "No solution" or "Infinitely many solutions.-6 product of (-12)(-8) 1 pointThe 5 consecutive integers below add up to 175. What is the value of x?x-3x-2X - 1X + 1 The first three terms of a sequence are given. Round to the nearest thousandth (ifnecessary).15, 18, 108/5. find the 8th term Atoms transfer from non living portions of our environment to the living part of our environment through the Can someone help me with this pls 2. Which is the volume of 3.20 moles of O?7. Which is the volume of 100. of O? when supplies are purchased on credit it means that: (check all that apply.) Kadeesha invested $900$900 in an account that pays 1.5% interest compounded annually. Assuming no deposits or withdrawals are made, find how much money Kadeesha would have in the account 11 years after her initial investment. Round to the nearest tenth (if necessary). Devon saw 19 adults wearing hats The molecular formula of Allicin, The compound responsible for the characteristics smell of garlic, is C6H 10 OS2. A) what is the molar mass of a Allicin?B) how many moles of allicin are present in 4.20 mg of the substance?C) how many molecules of Allicin are in 4.20 mg of the substance?D) how many C atoms are present in 4.20 mg of allicin? help me please I'm confused simplify -5mn 15m n The graph below shows three different normal distributions. 3 normal distributions are shown. All 3 are at different points on the axis. They all have different heights and widths. Which statement must be true? Each distribution has the same mean and the same standard deviation. Each distribution has the same mean and a different standard deviation. Each distribution has a different mean and the same standard deviation. Each distribution has a different mean and a different standard deviation. Mark this and return The fact that the voyager spacecraft continue to speed out of the solar system, even though its rockets have no fuel, is an example of. Simplify. 14(3x7)+34x Responses 34x1 3 over 4 end fraction x minus 1 334x134 3 and 3 over 4 end fraction x minus 1 and 3 over 4 34x+212 3 over 4 end fraction x plus 2 and 1 half 112x134 Given m||n, find the value of x.50Click heredismiss) Find the value of each variable