Answer:
Step-by-step explanation:
Given that X has the following pdf.
x -1 0 2 6 7 Total
P(X) 0.3 0.1 0.3 0.2 0.1 1
xP(X) -0.3 0 0.6 1.2 0.7 2.2
x^2P(X) 0.3 0 1.2 7.2 4.9 13.6
Var(x) 13.6-2.2^2 8.76
Std dev 2.959729717
5) 
6. Find the cumulative distribution function F(x) and calculate F(3.2) =
x -1 0 2 6 7
P(X) 0.3 0.1 0.3 0.2 0.1
F(x) 0.3 0.4 0.7 0.9 1
F(3.2) = P(X<3.2) = ___F(X<6) = 0.7__________
7. E(X) = ______2.2_____
8. Var(X) = ____8.76______
Answer:
degrees.
Step-by-step explanation:
Line ABC is a straight line, and the angle on a straight line is always 180 degrees.
Since ABD + DBC = ABC, we know that 
Divide both sides by 9:
DBC is 
degrees.
Add 3 to both sides so that the equation becomes -2x^2 + 5x + 5 = 0.
To find the solutions to this equation, we can apply the quadratic formula. This quadratic formula solves equations of the form ax^2 + bx + c = 0
x = [ -b ± √(b^2 - 4ac) ] / (2a)
x = [ -5 ± √(5^2 - 4(-2)(5)) ] / ( 2(-2) )
x = [-5 ± √(25 - (-40) ) ] / ( -4 )
x = [-5 ± √(65) ] / ( -4)
x = [-5 ± sqrt(65) ] / ( -4 )
x = 5/4 ± -sqrt(65)/4
The answers are 5/4 + sqrt(65)/4 and 5/4 - sqrt(65)/4..
