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

JaneDyan
Guest

Probability

Please help me with this problem:
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
Administrator
From: Bumpkinland
Registered: 2009-04-12
Posts: 86,302

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.
Of course that result can be rigorously obtained, but who cares?
Combinatorics is Algebra and Algebra is Combinatorics.

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

JaneDyan
Guest

Re: Probability

Thank you very much! smile

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
Administrator
From: Bumpkinland
Registered: 2009-04-12
Posts: 86,302

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.
Of course that result can be rigorously obtained, but who cares?
Combinatorics is Algebra and Algebra is Combinatorics.

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