Probability, MET2 2008 VCAA 14 MC The minimum number of times that a fair coin can be tossed so that the probability of obtaining a head on each trial is less than 0.0005 is A. `8` B. `9` C. `10` D. `11` E. `12` Show Answers Only `D` Show Worked Solution `text(Let)\ \ X = text(Number of heads,)` `X ∼ text(Bi) (n, 1/2)` `text(Pr) (X = n)` `< 0.0005` `((n), (n)) (1/2)^n (1/2)^0` `< 0.0005` `n` `> 10.97` `:. n_min = 11` `=> D`