Answer:
Step-by-step explanation:
The formula for the standard error of the difference between the estimates od the population proportions is:
This is expected, as the variance of a sum (or a substraction) of two random variables is equal to the sum of the variance of the two variables.
Then, the standard error (or standard deviation) is the square root of this variance.
8x=20
x=2.5
To check
8(2.5)=20
Minimum:58
maximum:90
median:70
lower quartile:63
upper quartile:81
interquartile range:18
Using the area of a rectangle, it is found that her patio should have a width of 12 feet and a length of 27 feet.
<h3>What is the area of a rectangle?</h3>
The area of a rectangle of length l and width w is given by:
A = lw.
In this problem:
- She has enough tiles to cover 324 square feet, hence A = 324.
- She wants the length of the patio to be 15 feet longer than the width, hence l = 15 + w.
Thus:
324 = w(15 + w)
w^2 + 15w - 324 = 0
w = -27 or w = 12.
We take the positive value, hence l = 15 + w = 15 + 12 = 27 feet.
The dimensions should be a width of 12 feet and a length of 27 feet.
You can learn more about the area of a rectangle at brainly.com/question/10489198