Question

There are twenty-three red marbles and two blue marbles in a box. a marble is randomly chosen from the box, its color noted, then put back in the box. this process is repeated. what is the probability that (a) the first marble is blue? (b) the first four marbles are red? (c) the first four marbles are red and the fifth is blue?

Answer 1

A. 2/25
B. 4/25
C. 6/25
I'm sure about the first one, not so much about the last 2 though...