There are 50 questions in an exam. A strudent's probability that he is unable to correctly answer less than 2 questions

In an examination, there are 3 multiple choice questions and each question has 4 choices. If a student randomly selects answer for all the 3 questions, what is the probability that the student will not answer all the 3 questions correctly ?

In an entrance examinations there are multiple choice question. There are five possible answers to each question of which one is correct. The probability that a student knows the answer to a question is 80%. IF he gets the correct answer to the question, then the probability that he was guessing is

In an entrance examinations there are multiple choice question. There are five possible answers to each question of which one is correct. The probability that a student knows the answer to a question is 80%. IF he gets the correct answer to the question, then the probability that he was guessing is

In an examination,10questions of true-false type are asked.A student tosses a fair coin to determinehis answer to each question.If the coin falls heads,he answers true and if it falls Lails,he answers true and if it probability that he answers at most correctly 7 questions is (121)/(128) .

In an entrance test, there are multiple choice questions. There are four possible answers to each question, of which one is correct. The probability that a student knows the answer to a question is 90%. If the gets the correct answer to a question, then find the probability that he was guessing.

In an entrance test, there are multiple choice questions. There are four possible answers to each question, of which one is correct. The probability that a student knows the answer to a question is 90%. If the gets the correct answer to a question, then find the probability that he was guessing.

In an entrance test, there are multiple choice questions. There are four possible answers to each question, of which one is correct. The probability that a student knows the answer to a question is 90%. If the gets the correct answer to a question, then find the probability that he was guessing.

In an entrance test,there are multiple choice questions.There are four possible answers to each question,of which one is correct.The probability that a student knows the answer to a question is 90%. If the gets the correct answer to a question,then find the probability that he was guessing.