box of 40 remote control devices contains 4 that have a defective power button. If devices are randomly sampled from the box and inspected one at a​ time, determine the following probabilities.   a. The probability that the first control device is defective. b. The probability that the first control device is good and the second control device is defective. c. The probability that the first three sampled devices are all good. I'm having difficulty finding out B. This is business statistics.

Which of the following statements is true about a random variable? Explain your reasoning. a. A random variable represents all outcomes of an experiment and their probabilities. b. A random variable represents any single random outcome from an experiment. c. A random variable is the probability of an experimental outcome. d. A random variable's value is unknown.

4. A geological study indicates that an exploratory oil well should strike oil with probability of 0.2. What is the probability that A. the first strike comes on the third well drilled? B. the third strike comes on the seventh well drilled? C. What assumptions did you make to obtain the answers to parts A and B? D. Find the mean and variant of the number of wells that must be drilled if the company wants to set up three producing wells.

We are interested in analyzing data related to college football. Use S to denote the team is in the SEC and use W to denote a team has a winning season. The probability that a team is in the SEC in the data set is 5.5%. The probability that a team has a winning season is 52.5%. The probability that a team is in the SEC and has a winning season is 3.55%. What percentage of teams are in the SEC or had a winning season? b. What percentage of people teams are in the SEC and did NOT have a winning season? Given a team had a winning season, what is the probability that they are in the SEC? а. с.