Yes, that is another way of getting it.

]]>Following the manner on how you solve the problem, I realized that the first question could also be answered by

getting the complement/not the probability of both wells producing oil:

1-.02=0.98

Welcome to the forum.

What is the probability that at most one well produces oil?

That can mean 0 or 1 so

.8 + .18 = .98

At least one?

That means 1 or 2 which is the complement of none.

1 - .8 = .2

]]>An oil-prospecting firm plans to drill 2 exploratory wells. Past evidence shows that the probability that neither well produces oil is 0.8; the probability that exactly one well produces oil is 0.18; and the probability that both wells produces is 0.02. What is the probability that at most one well produces oil? At least one?]]>