Using the counting method for the Monty Hall problem actually works very well. Initially there are 3 possible ways the goats and treasure can be arranged: goat

Using the counting method for the Monty Hall problem actually works very well. Initially there are 3 possible ways the goats and treasure can be arranged: goat goat treasure goat treasure goat treasure goat goat You pick a door -- let's say it's the first door. Monty opens one of the other 2 to reveal a goat, leaving one other door. This modifies the possible outcomes: goat treasure goat treasure treasure goat Using the counting approach, there is 1 outcome where door 1 has the treasure, and 2 outcomes where the other door has the treasure. 2/3 chance of finding the treasure if you switch.