Consider a box containing 30 red balls and 60 other balls that are either black or yellow.

You don't know how many black or yellow balls there are, but you know that the total number of black balls plus yellow balls equals 60 (e.g. could be 0 black 60 yellow or 60 black and 0 yellow or anywhere in-between.)

The balls are well mixed so that any individual ball is as likely to be drawn as any other.

Before drawing any balls you must make two decisions.

First you must choose between these two options:

A: You will receive $100 if you draw a red ball
B: You will receive $100 if you draw a black ball

You must also choose one of the following two options:

C: You will receive $100 if you draw a red or yellow ball
D: You will receive $100 if you draw a black or yellow ball

Did you pick A or B?
Did you pick C or D?
>(odds are you picked A and D and that's a paradox)