Random digits. Each entry in a table of random digits like Table B has probability 0.1 of being a 0, and digits are independent of each other.

(a) Suppose you want to determine the probability of getting at least one 0 in a group of five digits. Explain what is wrong with the logic of computing it as 0.1 1 0.1 1 0.1 1 0.1 1 0.1 or 0.5.

(b) Find the probability that a group of five digits from the table will contain at least one 0.

(c) In Table B, there are 40 digits on any given line.
What is the mean number of 0s in lines 40 digits long?