Hi, well I'm totally lost with this subject, and this is an easy question but I just don't understand ..
Question: A fair coint is flipped n = 100 times. What is the probability to have exactly k = 50 heads? What is the probability to have exactly n/2 heads when n is even?
Use the Classical Probability Model: with
<I don't understand why it is . Why isn't it just 100? >
<Again, I don't get why we're using the combination formula? Why isn't it just ...????>
Can someone please explain this to me?