Chapter 12, Problem 12.45E

a.

To determine

To identify: Whether the given random variable X (number of errors) is discrete or continuous.

To explain: The reason for identification.

b.

To determine

To write: The event “at least one non-word error” in terms of X.

To find: The probability of getting “at least one non-word error”.

c.

To determine

To describe: The event $X\le 2$ in words

To find: The probability of getting $X\le 2$ and also the probability of getting $X<2$.