claim: Your odds of correctly guessing the outcome of a flipped coin are 1 in 2, but your odds of guessing correctly twice in a row are only 1 in 4 —
evidence: Since the first four tosses turn up heads, the probability that the next toss is a head is : Pr (  A 5  |  A 1 ∩ A 2 ∩ A 3 ∩ A 4  ) = Pr (  A 5  ) = 1 2 { \displaystyle \Pr \left( A { 5 } | A { 1 }\cap A { 2 }\cap A { 3 }\cap A { 4 }
  ight )=\Pr \left( A { 5 }
  ight )={ rac { 1 }{ 2 } } } .