A test has 8 multiple choice questions, each with 4 choices. a. What is the probability of guessing 7 or more questions correctly? b. A test has 8 multiple choice questions, each with 5 choices. What...

Problem 4

Extracted text: A test has 8 multiple choice questions, each with 4 choices. a. What is the probability of guessing 7 or more questions correctly? b. A test has 8 multiple choice questions, each with 5 choices. What is the probability of guessing 4 or more questions correctly? C. A test has 8 multiple choice questions, each with 5 choices. What is the probability of guessing all 8 questions correctly? 4. A research team at Cornell University conducted a study showing that approximately 10% of all businessmen who wear ties wear them so tightly that they actually reduce the blood flow to the brain, diminishing cerebral functions (Source: Chances: Risks and Odds in Everyday Life, by James Burke). At a board meeting, 20 businessmen wear ties. a. Using the binomial formula, set up the probability that 12 businessmen wear ties that are tied too tightly and then simplify. 2.