Statistics & Data Analysis
A few examples of what you can ask Wolfram|Alpha about:
find sample size needed to estimate a binomial parameter
compute a confidence interval for a population mean
apply a test for a population mean
compute properties of a probability distribution
specify parameters for a distribution
compute a particular property
compute the expected value of a random variable
compute the probability of an event
compute the probability of a union of events
compute coin toss probabilities
compute odds for a poker hand
analyze a wager
compute the probabilities of shared birthdays for a group of people