For each situation below identify the population and the sample and identify p and p if appropriate and what the value of p is. Would you trust a confidence interval for the true proportion based on these data? Explain briefly why or why not.
a) As concertgoers enter a stadium, a security guard randomly inspects their backpacks for alcoholic beverages. Of the 130 backpacks checked so far, 17 contained alcoholic beverages of some kind. The guards want to estimate the percentage of all backpacks of concertgoers at this concert that contain alcoholic beverages.
b) The website of the English newspaper The Guardian asked visitors to the site to say whether they approved of recent “boss napping” actions by British workers who were outraged over being fired. Of those who responded, 49.2% said “Yes. Desperate times, desperate measures.”
c) An airline wants to know the weight of carry-on baggage that customers take on their international routes, so they take a random sample of 50 bags and find that the average weight is 17.3 pounds.