16BSC: Using the Binomial Probability Table. In Exercises, assume that random guesses are made for five multiple-choice questions on an ACT test, so that there are n = 5 trials, each with probability of success (correct) given by p = 0.20. Use the Binomial Probability table (Table A-1) to find the indicated probability for the number of correct answers. Find the probability that the number x of correct answers is at least 3.

Solution 16BSC: The goal is to use the given table to find the probability that the nu ber x of correct answers is at least 3. Step 1 of 3: In this problem, we are told that random guesses are made for five multiple-choice questions on the ACT test. So, there are n = 5 trials, each with probability of success given by p = 0.20. The phrase “at least 3 correct answers” means that the number of correct answers is 3 or 4 or 5. Step 2 of 3: The following excerpt from the table shows binomial probabilities when n = 5 and p = 0.20: