Can someone guide me with this question?

Question

Four teachers and five students have volunteered to serve on the school's fundraising committee, which is chaired by the principal. The principal wishes to select the committee using a random draw. He places each person's name on a slip of paper and draws four names.

a) What is the probability that atleast one teacher is on the committee?

how do you figure out if there is x amount of women, how many men there are? :S Help please, I have a quiz tomorrow :(

Answer 1

see other post.

Answer 2

What other post?

Answer 3

Anyone help?