SOLUTION: A fair coin is tossed 3 times. Find the probability of obtaining at least one head. a 7/8 b 1/4 c 1/2 d 1/6 e 5/6

Algebra ->  Probability-and-statistics -> SOLUTION: A fair coin is tossed 3 times. Find the probability of obtaining at least one head. a 7/8 b 1/4 c 1/2 d 1/6 e 5/6       Log On


   

Question 286762: A fair coin is tossed 3 times. Find the probability of obtaining at least one head.
a 7/8 b 1/4 c 1/2 d 1/6 e 5/6

Answer by Edwin McCravy(20060) About Me  (Show Source):
You can put this solution on YOUR website!

P(at least one head) = 1 - P(no heads) =

1 - P(tails 1st AND tails 2nd AND tails 3rd) =

"AND" indicates multiplication:

1 - P(tails 1st)*P(tails 2nd)*P(tails 3rd) =

1-%281%2F2%29%281%2F2%29%281%2F2%29=1-1%2F8=7%2F8

choice (a)

Edwin