(N+18)+2n=90
3n=90-18
3n=72
N=24
Yeah it’s b, you’re correct
Answer:
Mean = 2.14
Standard deviation = 2.40
Step-by-step explanation:
The calculation of mean and standard deviation is shown below:-

= 2.14
So, the mean is 2.14
Now, For computing the standard deviation first we need to find out the variance which is shown below:-
Variance is
![Var(X) = P(X^2) - [P(X)]^2\\\\ P(X^2) = .07\times (0^2) + .20\times (0^1) + .38\times (0^2) + .22\times (0^3) +0.13\times (0^4)](https://tex.z-dn.net/?f=Var%28X%29%20%3D%20P%28X%5E2%29%20-%20%5BP%28X%29%5D%5E2%5C%5C%5C%5C%20P%28X%5E2%29%20%3D%20.07%5Ctimes%20%280%5E2%29%20%2B%20.20%5Ctimes%20%280%5E1%29%20%2B%20.38%5Ctimes%20%280%5E2%29%20%2B%20.22%5Ctimes%20%280%5E3%29%20%2B0.13%5Ctimes%20%280%5E4%29)
After solving the above equation we will get
= 5.78
Now, the standard deviation is 

= 2.404163056
or
= 2.40
Step-by-step explanation:
The slope of a line characterizes the direction of aline. To find the slope, you divide the difference of the y-coordinates of 2 points on a line by the difference of the x-coordinates of those same 2 points .
Based on my created polygon, I formed a trapezoid.
I need to use the Pythagorean theorem to solve for the two sides that are the hypotenuse of the right triangles derived from the image.
1st side: distance from -1 to 5 = 6
2nd side: distance from -5 to 12 = 17
3rd side: hypotenuse:
a = -5 to -1 = 4
b = 0 t0 8 = 8
c² = 4² + 8² = 16 + 64 = 80
c = √80 = 8.94
4th side: hypotenuse:
a = 5 to 12 = 7
b = 0 to 8 = 8
c² = 7² + 8² = 49 + 64 = 113
c = √113 = 10.63
Perimeter = 6 + 17 + 8.94 + 10.63 = 42.57 or 42.6 units.