Which measure describes the standard error of the mean? A.
the central limit theorem
B.
the confidence interval
C.
the standard deviation of the means
D.
the sample mean

what is all that apply?

step-by-step explanation:

hans did not square the 40-unit side; he merely multiplied it by 2.   incorrect.

(b) 240

step-by-step explanation:

first, we use the pythagorean formula using the given side lengths to find x. then we use x to find the side lengths. then we add the side lengths to find the perimeter.

pythagorean theorem formula:

a^2 + b^2 = c^2

(x - 20)^2 + (x - 40)^2 = x^2

x^2 - 40x + 400 + x^2 - 80x + 1600 = x^2

x^2 -120x + 2000 = 0

(x - 100)(x - 20) = 0

x - 100 = 0 or x - 20 = 0

x = 100 or x = 20

we see that the solution x = 20 must be discarded because it will give a negative side length and a side length of 0. the only valid solution is x = 100.

perimeter = sum of the lengths of the sides

perimeter = x + x - 20 + x - 40

perimeter = 3x - 60

replace x with 100.

perimeter = 3(100) - 60

perimeter = 300 - 60

perimeter = 240

hi there!

step-by-step explanation:

a roof pitch is basically for every inch rise there is 12 inches run.

the height of the roof is also known as the rafter.

formula: rafter^2 = rise^2 + run^2

rafter^2 = 5^2 + 12^2

rafter^2 = 25 + 144

rafter ^2 = 169"^2

the height of the roof from the lowest point to the highest point is 169"^2.

hope this : )