SOLUTION: Flip a coin 10 times , what is the probability of not getting a head? What is the probability of getting a head at least 2 times?

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Question 1132047: Flip a coin 10 times , what is the probability of not getting a head?
What is the probability of getting a head at least 2 times?
Answer by ikleyn(52803) About Me  (Show Source):
You can put this solution on YOUR website!
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(a)   What is the probability of not getting a head? 

     %281%2F2%29%5E10 = 1%2F2%5E10 = 1%2F1024.       ANSWER


     By the way, it is THE SAME probability as of not getting a tail (!)


(b)   What is the probability of getting a head at least 2 times 

     The probability of getting a head at least 2 times is the COMPLEMENT to getting  a head not more than 1 time and is equal to


     1 - %28%281%2F2%29%5E10+%2B+C%5B10%5D%5E1%2A%281%2F2%29%2A%281%2F2%29%5E9%29 = 1 - %28%281%2F2%29%5E10+%2B+10%2A%281%2F2%29%5E10%29 = 0.9893 = 98.93%.     ANSWER