Answer to Question #307729 in Statistics and Probability for Kaikai

Question

Find the mean of the probability distribution of the random variable X, which can take only the values 3,5, and 7, given that P(3)= 7/30, P(5)=1/3, and P(3)= 13/30.

Answer 1

$\mu=3\cdot\cfrac{7}{30}+5\cdot\cfrac{1 }{3}+7\cdot\cfrac{13} {30} =$

$=\cfrac{3\cdot7+5\cdot10+7\cdot13} {30} =$

$=\cfrac{162} {30} =5.4.$