Quick probability question re: True/False exam questions Forum

[Geaux12]

So a portion of my exam Friday will include 35 True/False questions (ridiculously difficult, by the way). A correct response is awarded 2 points, an incorrect response is penalized 1 point, and leaving it blank results in 0 points awarded/subtracted.

Correct me if my math is wrong or I'm overlooking an important consideration, but as a matter of probability, I think it's in my best interest to answer every question, even if I don't know the answer.

For every three questions I answer, I should earn at least .5 points...right? And probably better than that?

This is, of course, assuming that there are equal numbers of T and F responses...which there almost certainly are not.


Anyone have some insight or advice (other than "study harder, dumbass")?

[lawhopeful10]

So a portion of my exam Friday will include 35 True/False questions (ridiculously difficult, by the way). A correct response is awarded 2 points, an incorrect response is penalized 1 point, and leaving it blank results in 0 points awarded/subtracted.

Correct me if my math is wrong or I'm overlooking an important consideration, but as a matter of probability, I think it's in my best interest to answer every question, even if I don't know the answer.

For every three questions I answer, I should earn at least .5 points...right? And probably better than that?

This is, of course, assuming that there are equal numbers of T and F responses...which there almost certainly are not.


Anyone have some insight or advice (other than "study harder, dumbass")?

I'm pretty sure your math is right so if you didn't know the answer you should guess. To double check though assume there are 10 questions you don't know. If you don't answer them that's 0 points. If you get half right and half wrong you would get 5 points total (10-5). Thus guessing seems to be the way to go if you need too lol.

[ScottRiqui]

The Expected Value of leaving a question blank is zero points:

100% ( 0 ) = 0


The EV of guessing is a half-point:

50% (2) + 50% (-1) = +0.5

Over the course of many guesses, even a coin flip is better than leaving the question blank.

[helfer snooterbagon]

Best bet is to get them all correct.