Conference's attendees may optionally register for an additional workshop; assume that each conference has 220 attendees and that the probability of any given attendee attending the workshop is 15%.:

First, figure out which type of probability distribution applies here.

For this question, I'm confused which type of distribution must be found.

Although it provides some probability, there a no indication on mean or deviation.

b. Calculate the expected (or mean) number of workshop attendees out of the 220 at the conference and the variance of number of attendees of such workshops over multiple conferences.

c. Give the probability that a given workshop has fewer than 4 attendees.