I'll just do part (a). Try using the same principle to do part (b) by
yourself. If you have trouble, tell me in the thank-you note form below
and I'll get back to you by email.
A game is such that a fair die is rolled repeatedly until a '6' is obtained. Find the probability that
(a) (i) the game ends on the third roll,
(ii) the game ends on the fourth roll,
(iii) the game ends by the fourth roll.
We add the probabilities of the four mutually exclusive events,
using the same procedure above to calculate the probabilities
that the games end on the 1st roll or 2nd roll, and use the above
two probabilities for it ending on the 3rd or 4th
Edwin
