SOLUTION: 6. The random variable X has the following probability distribution: X 0 1 2 3 P(x) 0.2 0.1 0.4 K a. Find K to Prove that the given table satisfied a probability distributio

Algebra ->  Probability-and-statistics -> SOLUTION: 6. The random variable X has the following probability distribution: X 0 1 2 3 P(x) 0.2 0.1 0.4 K a. Find K to Prove that the given table satisfied a probability distributio      Log On


   

Question 1074133: 6. The random variable X has the following probability distribution:
X 0 1 2 3
P(x) 0.2 0.1 0.4 K
a. Find K to Prove that the given table satisfied a probability distribution
b. Find the mean & the Variance.

Answer by rothauserc(4718) About Me  (Show Source):
You can put this solution on YOUR website!
The summation from i = 1 to 4 of P(x) must = 1, therefore
:
a) K = 1 - (0.2 + 0.1 + 0.4) = 0.3
:
b)mean = (0 + 1 + 2 + 3) / 4 = 1.5
:
Variance = ( (0 - 1.5)^2 + (1 - 1.5)^2 + (2 - 1.5)^2 + (3 - 1.5)^2 ) / 4 = 1.25
: