Suppose you roll 4 dice.

a) What is the probability that you get 4 different numbers?

b) What is the probability that you get '2 pairs' (two of one number and
two of another number?)

c) Now suppose that you continue rolling 4 dice over and over until you get
either get '4 different numbers' or 'two pairs'. What is the probability
that you get 'two pairs' first?

Dear xotica

Here is a LINK to a website where you can find all the info you need to answer these questions. (http://mathforum.org/library/drmath/sets/select/dm_dice.html)

Success !

:)

b) What is the probability that you get '2 pairs' (two of one number and
two of another number?)

Count them up. Let's pair them.

1122, 1133,1144,1155,1166,2233,2244,2255,2266,3344,3355, 3366,4455,4466,5566

Each of these can be arranged in 6 ways.

(15)(6)=90

There are 6^{4}=1296 total arrangements.

Does anyone know c?