Chapter 4: Probability

The probability of getting exactly 500 heads in 1000 tosses is 0.0252. Is this result unlikely? Is 500 heads unusually low or unusually high? Rare Event Rule: Ex: In a clinical experiment of the Salk vaccine for polio, 200,745 children were given the placebo and 201,229 were given the vaccine. There were 115 cases of polio among those in the ... ................
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