Question

If you flip a coin twice, what is the probability that you will get heads one time and tails one time?

Answer 1

For the first coin, it could be either head or tail. So the probability is 1.

For the second coin, it has to be the opposite of the first. So the probability is 0.5

Multiply the two and you get 0.5, or as the common folks called it, "50/50".

It doesn't matter if you use one coin and flip it twice or two coins and flip each on once.

It does matter, however, if you dictate that the first one must be head and the second one must be tail, or the first one must be tail and the second one must be head. Then the probability becomes 0.25, or one in four.