An 80% confidence interval for a proportion is found to be (0.52, 0.56). What is the margin of error?

Which of the following is equivalent<br> to the product of 4.3 million and<br> 2.1 million?

Solnce55 [7]

What are the answer choices?

7 0

2 years ago

An oil refinery is located on the north bank of a straight river that is 2 km wide. A pipeline is to be constructed from the ref

hichkok12 [17]

Answer:

P is exactly 3km east from the oil refinery.

Step-by-step explanation:

Let's d be the distance in km from the oil refinery to point P. So the horizontal distance from P to the storage is 3 - d and the vertical distance is 2. Hence the diagonal distance is:

$\sqrt{(3 - d)^2 + 2^2} = \sqrt{(3 - d)^2 + 4}$

So the cost of laying pipe under water with this distance is

$800000\sqrt{(3 - d)^2 + 4}$

And the cost of laying pipe over land from the refinery to point P is 400000d. Hence the total cost:

$800000\sqrt{(3 - d)^2 + 4} + 400000d$

We can find the minimum value of this by taking the 1st derivative and set it to 0

$800000\frac{2*0.5*(3-d)(-1)}{\sqrt{(3 - d)^2 + 4}} + 400000 = 0$

We can move the first term over to the right hand side and divide both sides by 400000

$1 = 2\frac{3 - d}{\sqrt{(3 - d)^2 + 4}}$

$\sqrt{(3 - d)^2 + 4} = 6 - 2d$

From here we can square up both sides

$(3 - d)^2 + 4 = (6 - 2d)^2$

$9 - 6d + d^2 + 4 = 36 - 24d + 4d^2$

$3d^2-18d+27 = 0$

$d^2 - 6d + 9 = 0$

$(d - 3)^2 = 0$

$d -3 = 0$

d = 3

So the cost of pipeline is minimum when P is exactly 3km east from the oil refinery.

3 0

3 years ago

4-0.25+9.5h when g=10 and h=5

Furkat [3]

N sei só quero ponto

6 0

3 years ago

Add (minus 2x+4) + (5x+2)

Anuta_ua [19.1K]

Answer:

3x + 6 or 3( x + 2 )

Step-by-step explanation:

5x - 2x = 3x

4 + 2 = 6

7 0

3 years ago

A mesuré of_____ for a numerical data set summerizes all of its values with a single number????

hammer [34]

Answer:

Center

Step-by-step explanation:

A numerical data can be defined as a data set that is expressed in numbers only or a data set consisting of numbers rather than words. A numerical data is also known as a quantitative data.

Basically, numerical data are classified into two (2) main categories and these are;

1. Discrete data: a discrete data is a data set in which the number of possible values are either finite or countable. For instance, the value of a fair die, number of sweets in a jar, number of eggs in a crate etc.

2. Continuous data: a continuous data is a data set having infinitely many possible values and those values cannot be counted, meaning they are uncountable. Any quantity such as height, volume, weight, density, length, pressure, temperature, speed, distance, time are generally a continuous data.

A measure of center for a numerical data set summerizes all of its values with a single number.

On the other hand, a measure of variation gives a description of how the values of a numerical data varies with a single number.

4 0

2 years ago