Duplicate Question
The question on this page has been marked as a duplicate question.
Original Question
You have a friend who claims to be psychic. You don't believe this so you test your friend by flipping a coin 20 times and havi...Asked by j
You have a friend who claims to psychic. You don't believe this so you test your friend by flipping a coin 20 times and having him predict whether each flip is heads of tails. If you are right, and your friend is NOT psychic, then the probability of guessing correctly on each flip is .5. Your friend correctly guesses 15 out of the 20 flips.
What is the probability of your friend correctly guessing 15 or more out of 20 flips if he is NOT really psychic?
What is the probability of your friend correctly guessing 15 or more out of 20 flips if he is NOT really psychic?
Answers
mathhelper
prob of getting 15 of 20 correct
= C(20,15) (1/2)^20 = 15504/1048576 = .014785..
So what is your conclusion?
= C(20,15) (1/2)^20 = 15504/1048576 = .014785..
So what is your conclusion?