1answer.
Ask question
Login Signup
Ask question
All categories
  • English
  • Mathematics
  • Social Studies
  • Business
  • History
  • Health
  • Geography
  • Biology
  • Physics
  • Chemistry
  • Computers and Technology
  • Arts
  • World Languages
  • Spanish
  • French
  • German
  • Advanced Placement (AP)
  • SAT
  • Medicine
  • Law
  • Engineering
pshichka [43]
3 years ago
5

A researcher is interested in estimating the mean weight of a semi trailer truck to determine the potential load capacity. She t

akes a random sample of 17 trucks and computes a sample mean of 20,000 pounds with sample standard deviation of 1,500. The 95% confidence interval for the population mean weight of a semi trailer truck is ______________.
Mathematics
1 answer:
Kaylis [27]3 years ago
3 0

Answer: 95% confidence interval = 20,000 ± 2.12\times\frac{1500}{\sqrt{17} }

( 19228.736 , 20771.263 ) OR ( 19229 , 20771 )

Step-by-step explanation:

Given :

Sample size(n) = 17

Sample mean = 20000

Sample standard deviation = 1,500

5% confidence

∴ \frac{\alpha}{2} = 0.025

Degree of freedom (d_{f}) = n-1 = 16

∵ Critical value at ( 0.025 , 16 ) = 2.12

∴ 95% confidence interval = mean ± Z_{c}\times\frac{\sigma}{\sqrt{n} }

Critical value  at 95% confidence interval = 20,000 ± 2.12\times\frac{1500}{\sqrt{17} }

( 19228.736 , 20771.263 ) OR ( 19229 , 20771 )

You might be interested in
In a certain year, there were 88 female officials in Congress, which is comprised of the House of Representatives and the Senate
Ainat [17]

Answer:

  • 71 in House of Representatives
  • 17 in Senate

Step-by-step explanation:

Let h and s represent the numbers in the House and Senate, respectively. Then we have ...

  h + s = 88

  h - s = 54

Subtracting the second equation from the first gives ...

  (h +s) -(h -s) = (88) -(54)

  2s = 34 . . . . . simplify

  s = 17 . . . . . . . divide by 2

  h = 88 -17 = 71 . . . . find the other value using the sum equation

There were 71 females in the House of Representatives, and 17 females in the Senate.

3 0
2 years ago
Marketing Chapter 3 Test Questions
butalik [34]

Step-by-step explanation:

1.) The average nightly ticket sales can be calculated as

Average sales = Average no. of customers per night x Charge per ticket

For the second night, we have

$1750 = (N)($7)

This gives us N = 250.

So, the average number of customers decreased as a result of the price increase.

To calculate the percentage change, we use the following formula:

% change = \frac{250 -300}{300} X 100

We have -17% change in the average number of customers the theater has each night. The negative sign indicates a decrease in the number, which is consistent with our calculations.

2.) % change in prices = \frac{Final price - Initial price}{Initial price} X100

Therefore, we have 40% change in the cost of ticket per person, which reflects an increase in the prices.

3.) Elasticity of Demand = \frac{ percentage change in quantity demanded}{percentage change in price}

Hence, we have \frac{-17}{40} = -0.425

This stands consistent with the Law of Demand - as the price increases, the quantity demanded decreases.

4.) Market price is obtained by looking for a point where the quantity supplied equals the quantity demanded. From the table we see that at $75 price, there is a demand for 45,000 units of that product in that market, which the suppliers are willing to supply. Hence, that defines the market price for that product.

6 0
3 years ago
The net of a square pyramid is shown in the diagram.
lana66690 [7]

Answer:

23

Step-by-step explanation:

5 0
2 years ago
Read 2 more answers
How do I solve this equation? I need a refresher on Algebra.
PilotLPTM [1.2K]
These equations seem tricky, but aren't as hard as you think. Just solve it like you are regularly adding fractions.

Your common denominator is 9x + 9, so

1/(9x+9)  =  36/(9x + 9)   -    (5x + 5)/9

1 - 36 + 5x + 5 / 9x - 9
30x - 30/9x - 9
10x-10/3x - 3
10(x-1)/3(x-1)
10/3

Hope this helped!
6 0
3 years ago
In major league soccer, standings are determined by points. Three points are awarded for each win, 1 point is awarded for each t
Vlada [557]

Answer:

They won 17 games and drew 4 games

Step-by-step explanation:

The given parameters are;

The number of points the major league soccer team finished with = 55 points

The number of games the soccer team played = 28 games

The number of losses the soccer team had = 7 losses

The number of points awarded for each win = 3 points

The number of points awarded for each tie = 1 points

The number of points awarded for each loss = 0 points

Let x represent the number of wins, y represent the number of draws, and let z represent the number losses

Therefore;

z = 7

x + y + z = 28

3·x + y + 7×0 = 55

Therefore, we have the following system of equations;

x + y = 21...(1)

3·x + y = 55...(2)

Which gives;

\begin{bmatrix}1 & 1\\ 3 & 1\end{bmatrix} \begin{bmatrix}x \\ y\end{bmatrix} = \begin{bmatrix}21 \\ 55\end{bmatrix}

The inverse of the matrix is given as follows;

\dfrac{1}{1 - 3}  \times \begin{bmatrix}1 & -3\\ -1 & 1\end{bmatrix} = \begin{bmatrix}-0.5 & 0.5\\ 1.5 & -0.5\end{bmatrix}

Therefore;

\begin{bmatrix}x \\ y\end{bmatrix} = \begin{bmatrix}-0.5 & 0.5\\ 1.5 & -0.5\end{bmatrix}  \times  \begin{bmatrix}21 \\ 55\end{bmatrix}  =  \begin{bmatrix}17 \\ 4\end{bmatrix}

x = 17, y = 4

3 0
2 years ago
Other questions:
  • Drag the item from the item bank to its corresponding match.
    9·1 answer
  • The sum of 4x and 7 is less than or equal to 39.<br><br> PLS HELP
    8·1 answer
  • What is the answer and you are finding the volume. Use 3.14 for pi
    6·1 answer
  • The random numbers below represent 15 trials of a basketball simulation conducted using a spinner numbered 0–8. 76645, 46757, 28
    11·1 answer
  • What angel do the minute and hour hands of s clock make at 9:00?
    13·1 answer
  • Can the product of 4 and any number always be written as a sum of two equal addends
    14·1 answer
  • Arrange the equations in increasing order of the value of their solutions.
    12·2 answers
  • Is the following sequence a geometric sequence?<br><br> 4, 12, 36, 108
    6·1 answer
  • The scatter plot presents Ray’s monthly electricity bills and the amount of time Tay spent at home from January through August.
    13·2 answers
  • Find the Surface Area of the cylinder
    8·2 answers
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!