Suppose now I have two BIASED coins in two containers (4 coins in total).

Container 1's coins have a probability of L1 of getting heads and Container 2's coins have a probability of L2 of getting heads. L1 is not equal to L2.

Which will give a higher chance of getting two heads if I:

a) Select one container at random then toss the two coins in it

b) Toss one coin each from each container

Please guide me and give me hints. I want to come up with the solution myself!

For a start, this is about conditional probability, right?

Also, I think option A will give a higher chance, but I'm not sure if I'm correct.

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