Question

I toss an unfair coin 12 times. This coin is 65% likely to show up heads. What is the probability of getting 6 tails?

Answer 1

P( tail) = 1 - 0.65 = 0.35

X ~ Bin ( n , p)

Where n = 12 , p = 0.35

Binomial probability distribution is

P(X) = nCx px ( 1 - p)n-x

So,

P(X = 6) = 12C6 * 0.356 * ( 1 - 0.35)6

= 0.1281