For a question on probability the student's answer was `3/2` . The teacher told that the answer was wrong. Why ?

In a competitive examination, an examinee either guesses or copies or knows the answer to amultiple choice question with four choices. The probability that he makes a guess is 1/3 and the probability that he copies the answer is 1/6. The probability that the answer is correct, given that he copiedit, is 1/8 . Find the probability that he knows the answer to the question, given that he correctly answered

In a competitive examination, an examinee either guesses or copies or knows the answer to amultiple choice question with four choices. The probability that he makes a guess is 1/3 and the probability that he copies the answer is 1/6. The probability that the answer is correct, given that he copiedit, is 1/8 . Find the probability that he knows the answer to the question, given that he correctly answered

In answering a question on a multiple choice test, a student either knows the answer or guesses. Let 3/4 be the probability that he knows the answer and 1/4 be the probability that he guesses. Assuming that a student who guesses at the answer will be correct with probability 1/4 . What is the probability that the student knows the answer given that he answered it correctly ?

In answering a question on a multiple choice test, a student either knows the answer or guesses. Let (3)/(4) be the probability that he knows the answer and (1)/(4) be the probability that he guesses. Assuming that a student who guesses at the answer will be correct with probability (1)/(4) What is the probability that the student knows the answer given that he answer it correctly?

On a multiple-choice exam with 3 possible destructive for each of the 5 questions, the probability that a student will get 4 or more correct answers just by guessing is

In a multiple choice question, there are four alternative answers of which one or more than one is correct A candidate will get marks on the question only if he ticks the correct answer. The candidate decides to tick answers at a random. If he is allowed up to three chances to answer the question, then find the probability that he will get marks on it.

If odds against solving a question by three students are 2:1, 5:2, and 5:3, respectively, then probability that the question is solved only by one student is a. 31//56 b. 24//56 c. 25//56 d. none of these

In an examination 20 questions of true false type are asked. Suppose a student tosses a fair coin to determine his answer to each question. If the coin falls head, he answers 'true', if it falls tail, he answers 'false'. Find the probability that he answers atlest 12 questions correctly.