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
mihalych1998 [28]
3 years ago
15

A study has indicated that the sample size necessary to estimate the average electricity use by residential customers of a large

western utility company is 900 customers. Assuming that the margin of error associated with the estimate will be ±30 watts and the confidence level is stated to be 90 percent, what was the value for the population standard deviation?
Mathematics
1 answer:
Zanzabum3 years ago
7 0

Answer:

\sigma=547.1125

Step-by-step explanation:

-The margin of error is calculated using the formula:

ME=z_{\alpha/2}\times \frac{\sigma}{\sqrt{n}}\\\\

-We substitute the values, n=900 and ME=30 in the formula to solve for standard deviation:

ME=z_{\alpha/2}\times \frac{\sigma}{\sqrt{n}}\\\\\\30=1.645\times\frac{\sigma}{\sqrt{900}}\\\\\sigma=\frac{30^2}{1.645}\\\\=547.1125

Hence, the population standard deviation is 547.1125

You might be interested in
Do 6 and 7 please vote you brainiest
tiny-mole [99]

The anser for 6 is 25/92

The answer for 7 is 1 1/2

6 0
3 years ago
The height of bamboo is proportional to its age. Use the graph to determine how long it takes for bamboo to reach a height of 12
Brut [27]

Answer:

Answer: 30 weeks

wosejdjdduddd

4 0
2 years ago
What is the answer <br>7(2m+5)​
ira [324]

Answer:

14m+35 is your answer ☺️☺️☺️

6 0
2 years ago
Read 2 more answers
Which equation represents a line that is perpendicular to line PQ?
valentinak56 [21]

Answer:

B. y=1/3x+4

Step-by-step explanation:

Hi there!

We are given the line PQ and we want to find the line that is perpendicular to it

Perpendicular lines have slopes that are negative and reciprocal. When they are multiplied together, the result is -1

So first, let's find the slope of the line PQ

The point P is given as (-8, 7) and the point Q is given as (-4, -5)

The formula for the slope calculated from two points is \frac{y_2-y_1}{x_2-x_1} where (x_{1} y_1) and (x_2, y_2) are points

We have the needed information for the slope, but let's label the values of the points to avoid any confusion

x1=-8

y1=7

x2=-4

y2=-5

Now substitute into the formula (m is the slope, and remember: the formula contains SUBTRACTION):

m=\frac{(-5-7)}{(-4--8)}

simplify

m=\frac{-5-7}{-4+8}

add

m=-12/4

divide

m=-3

So the slope of the line PQ is -3

As said above, perpendicular lines have slopes that have a product of -1

So to find the slope of the line perpendicular to PQ, use this formula:

-3m=-1

divide both sides by -3

m=1/3

The only line that has a slope of 1/3 is B (y=1/3x+4), so B is the answer.

Hope this helps!

3 0
3 years ago
A little help please
DaniilM [7]

Answer:

x = 30

Step-by-step explanation:

by solving ;

  • 18 / x = 6 / 10
  • 1 / x = 6 / ( 18 × 10 )
  • 1 / x = 6 / 180
  • 1 / x = 1 / 30
  • x = 30

4 0
3 years ago
Other questions:
  • the larger of two numbers is eight more than the smaller number. their sum is twenty-two. find the number
    5·1 answer
  • PLEASE HELP ME!!!!!!
    9·1 answer
  • A bag has 2 blue marbles, 3 red marbles, and 5 white marbles. Which events have a probability greater than 1/5? Check ALL that a
    10·1 answer
  • I need help with these questions
    12·1 answer
  • What is 1 5/8 plus 3 3/4?
    9·1 answer
  • Hi how are you today also bye
    7·2 answers
  • Find the equation of the linear function represented by the table below in slope
    5·1 answer
  • 3. the quotient of -9 and y
    11·1 answer
  • Using the rate of Rs 105 per US Dollar, calculate<br>the US Dollars for Rs 21000.​
    6·2 answers
  • Solve the proportion for x
    8·1 answer
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!