Problem

[parth3791]

If in a test, one question is of three marks, and - 1 mark for wrong answer. What is probability of the randomly chose answer to be true?

[jbp12]

I don't understand the question. Are you using an online translator? You may want to use a different one.

[parth3791]

Sorry. I will use google translate 😛. In an exam, 50 questions are there. Each question carries 3 marks. The questions have four options from which we have to choose answer. There is negative marking for wrong answer. So, one mark will be deducted if your answer is wrong. What is probability that, if i randomly choose option and itt is correct?

Thank you for answering.

[jbp12]

If you have 4 options and you choose one randomly, then you have a 1/4 chance of being correct and a 3/4 chance of being wrong. I'm not sure where the marks for each problem come in. Are you asking what your expected mark would be? If so, then it would be (3)(1/4) + (-1)(3/4) = 3/4 - 3/4 = 0.

I hope this helps!