keithe@teklabs.UUCP (08/19/83)
Let me expand on Ken Turkowski's explanation:
After you select a gold coin, you have the following possible
systems:
Possibility 1:
G1 in hand
------------- -------------
| | | |
| empty | | G3 |
| | | |
------------- -------------
| | | |
| G2 | | S3 |
| | | |
------------- -------------
Possibility 2:
G2 in hand
------------- -------------
| | | |
| G1 | | G3 |
| | | |
------------- -------------
| | | |
| empty | | S3 |
| | | |
------------- -------------
Possibility 3:
G3 in hand
------------- -------------
| | | |
| G1 | | empty |
| | | |
------------- -------------
| | | |
| G2 | | S3 |
| | | |
------------- -------------
Now you can see that there are 2 out of 3 chances of
selecting a gold coin from the other drawer.