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Question: 2019 Winter Final - 19

Author: Michiel Smid
A red box contains the numbers 0, 1, and 2; a blue box contains the numbers 0 and 1; and a green box contains the numbers 1 and 2. Consider the following two steps: Step 1: Choose a uniformly random number from the red box, and denote it by $x$.
Step 2:
  • If $x = 0$ or $x = 2$, then choose a uniformly random number from the green box, and denote it by $y$.
  • Otherwise (i.e., if $x = 1$), choose a uniformly random number from the blue box, and denote it by $y$.
Consider the random variables
  • X = the number $x$ you choose in Step 1,
  • Y = the number $y$ you choose in Step 2,
  • Z = $\max(X,Y).$
What is the expected value $\mathbb{E}(Z)$ of the random variable $Z$?
(a)
1
(b)
3/2
(c)
2
(d)
None of the above.