The Bag Game

Each bag below has lots of counters in it, coloured either blue or yellow.

In this game you choose a bag, and remove one counter at random. If you get a blue counter you win £20 (this is pretend – no-one is going to send you £20!), if you get a yellow counter you don’t win.

But there are some additional rules:
If you choose Bag A you get a guaranteed chocolate bar regardless of what counter you draw.
If you choose Bag B you don’t get a chocolate bar, but you do get a 50% higher chance of getting a blue counter.

Decide which bag you would like to choose!

CLICK on the bag to ‘choose’ it. Did you win? (Then scroll down to see more).

Thinking about the game:

To make an informed decision in this game we need to know our absolute chances of winning in Bag A and B, not just the chance of Bag B relative to Bag A.

Use the game to estimate the probability of winning in Bag A.

Now you have estimated the probability of winning with bag A, which do you think is the best choice?