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Discrete random variables

Hugo plans to buy packs of baseball cards until he gets the card of his favorite player, but he only has enough money to buy at most four packs. Suppose that each pack has probability 0.20.2 of containing the card Hugo is hoping for.
The table below displays the probability distribution of XX, the number of packs of cards Hugo buys.
XX11223344
P(X)P(X)0.20.20.160.160.1280.1280.5120.512
Find the expected value of the number of packs of baseball cards that Hugo buys.
Round your answer to the nearest thousandth.
  • Your answer should be
  • an integer, like 66
  • a simplified proper fraction, like 3/53/5
  • a simplified improper fraction, like 7/47/4
  • a mixed number, like 1 3/41\ 3/4
  • an exact decimal, like 0.750.75
  • a multiple of pi, like 12 pi12\ \text{pi} or 2/3 pi2/3\ \text{pi}
packs