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2015 AMC 10B Question 18

AMC10 · 2015 AMC 10B

Question 18

Johann has $64$ fair coins. He flips all the coins. Any coin that lands on tails is tossed again. Coins that land on tails on the second toss are tossed a third time. What is the expected number of coins that are now heads?
  1. $ 32 $
  2. $ 40 $
  3. $ 48 $
  4. $ 56 $
  5. $ 64 $