SOLUTION: Please help me solve the following question.
The random variable X has the following distribution.
x = -1, 9, 1, 2
P(X=x) 3c, 2c, 0.4, 0.1
Find the variance and standard de
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-> SOLUTION: Please help me solve the following question.
The random variable X has the following distribution.
x = -1, 9, 1, 2
P(X=x) 3c, 2c, 0.4, 0.1
Find the variance and standard de
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Question 1081927: Please help me solve the following question.
The random variable X has the following distribution.
x = -1, 9, 1, 2
P(X=x) 3c, 2c, 0.4, 0.1
Find the variance and standard deviation. Answer by Boreal(15235) (Show Source):
You can put this solution on YOUR website! The value of c can be determined. We know that 3c+2c=0.5 and 5c=0.5, so c=0.1 and the probability of x=-1 is 0.3, x=9 is 0.2, x=1 is 0.4 and x=2 is 0.1
E(X)=-0.3+1.8+0.4+0.2=2.1
V(X)=(x-E(X))^2*p(x)
-3.1^2*0.3=2.883
6.9^2*0.2=9.522
1.1^2*0.4=4.84
0.1^2*0.1=0.001
They add to 17.246
sd is sqrt (V)=4.153
