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## #1 2012-12-13 11:17:27

JaneDyan
Guest

### Probability

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?

## #2 2012-12-13 12:10:49

bobbym

Offline

### Re: Probability

Hi JaneDyan;

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

In mathematics, you don't understand things. You just get used to them.
I have the result, but I do not yet know how to get it.
All physicists, and a good many quite respectable mathematicians are contemptuous about proof.

## #3 2012-12-13 12:47:45

JaneDyan
Guest

### Re: Probability

Thank you very much!

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

## #4 2012-12-13 12:50:56

bobbym

Offline

### Re: Probability

Hi JaneDyan;

Yes, that is another way of getting it.

In mathematics, you don't understand things. You just get used to them.
I have the result, but I do not yet know how to get it.
All physicists, and a good many quite respectable mathematicians are contemptuous about proof.