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noreturn2
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Homework Statement
f(x) = (3/4)(-x^2 + 6x - 8) for 2 < x < 4 (0 elsewhere)
A) Find F(x)
integral 2 to 4 ((3/4)(-x^2 + 6x - 8))dx
B) Use F(x) to find P(3 < X < 3.5)
integral 3 to 3.5 ((3/4)(-x^2 + 6x - 8))dx
11/32
C) Use F(x) to find P(X > 3.5)
1-( P(3 < X < 3.5)) = 21/31
D) Find E(X).
integral 2 to 4 (x*(3/4)(-x^2 + 6x - 8))dx = 3
E) Find the standard deviation of X.
integral 2 to 4 (x^2(3/4)(-x^2 + 6x - 8))dx E[x^2)-E[x] = sqrt(6.2)= 2.48