Quantcast XP Math - Forums - View Single Post - A coin is tossed five times. Find the probability of getting exactly three heads.?
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Old 07-26-2007   #2
rrabbit
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You have to get three heads and two tails, and there is more than one way of doing this. The formula isp(3) = 5C3 × 0.5^3 × 0.5^2where 5C3 = 5!/3!2! = 10 is the number of ways of selecting 3 things out of 5.This gives the probability of exactly three heads as 0.3125..