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## #1 2012-12-12 12:17:27

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 2012-12-12 13:10:49

bobbym
bumpkin
From: Bumpkinland
Registered: 2009-04-12
Posts: 109,606

### 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.
If it ain't broke, fix it until it is.
Always satisfy the Prime Directive of getting the right answer above all else.

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## #3 2012-12-12 13:47:45

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 2012-12-12 13:50:56

bobbym
bumpkin
From: Bumpkinland
Registered: 2009-04-12
Posts: 109,606

### 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.
If it ain't broke, fix it until it is.
Always satisfy the Prime Directive of getting the right answer above all else.

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