What is the expected value of X 050 062 026 022 Use the tree

What is the expected value of X? 0.50 0.62 0.26 0.22 Use the tree diagram to find the requested probability. Find P(X|A). Give your answer as a decimal and if necessary. 0.12 0.109 0.197 0.4

Solution

P(X/A) =P(X intersection A)/P(A)

P(X intersection A) = a*c=.3 *.4=.12

P(A)= a*c + b*e = .3*.4 + .7*.7=.61

P(X/A)= .12/.61= .197

Correct option is C