Originally Posted by
ataraxis
err, you obviously dont get what I'm saying here. Say that Wendylove gave a 1 question test, the question was
"How many states are there in the US"
A) 49
B) 50
C) 124
Of course, SHE would say that its 49, because Texas isn't a state, of course.
So by the logic you are presenting, if 99 people took the test, 33 would get a 100, the rest would fail. Now, this is obviosuly untrue. Most people would say B, 50, so they would get it wrong.
So people can easily get a 0. If they are guessing, as you said, there is a very small chance of them getting a 0. But most people would choose, but choose wrong.
Basically, Xie, probability like that only applies when each answer has an equal chance of being picked. In your "random guessing" example, yes, each answer has an equal chance. However, when there is a universal inclination to pick one answer, (for example, everyone 'knows' that there are 50 states, but in this example test that is the wrong answer), then the balance is greatly shifted and your estimated probability of getting a 0 is 'completely wrong'