A college graduate statistics class has eighteen students. The ages of these students are as follows: one student is 18 years old, two are 20, nine...

A college graduate statistics class has eighteen students. The ages of these students are as follows: one student is 18 years old, two are 20, nine are 22, three are 24, two are 29, and one is 40. Let X = age of any student (randomly selected). Find the probability mass function of X
Five thousand instant lottery tickets were sold. One ticket has a face value of $10,000, five tickets have face values of $1000 each, twenty tickets are worth $500 each, thirty tickets have face value of $100 each, and 500 are worth $1.00 each. The rest are losers. Let X= the value of a ticket that you buy. Find the Probability mass function for X.
Flying Express Airlines flight 82 from Dallas to Miami is on time 85% of the time, according to FLying Express Airlines. Suppose sixty-five fights are randomly selected.
What does the random variable X represent?
What is the distribution of the random variable X?
How many flights from dallas to miami would you expect to arrive on time?