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Jason inherited a piece of land from his great-uncle. Owners in the area claim that there is a 45% chance that the land has oil. Jason decides to test the land for oil. He buys a kit that claims to have an 80% accuracy rate of indicating oil in the soil. What is the probability that the land has no oil and the test predicts it has oil?

2 Answers

2 votes

Answer:

Don't take my word for it but I think it would be 55% chance. I'm Probably wrong.

Explanation:

User Shahbaz Ali
by
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1 vote

Answer:

9% or 0.09

Explanation:

Given, chance of land having oil is 45%. Which is 0.45

So, chance of land NOT having oil is percent. Which is 0.55

Given, kit's accuracy rate of finding oil as 80%. Which is 0.80

So, kit's accuracy rate of NOT finding oil is percent. Which is 0.20

These 2 events are INDEPENDENT, which means that the probability of one event occurring does not affect the probability of another event occuring.

The formula, if we let the two evens be A and B, is:

P(A and B)=P(A) * P(B)

Now, "the probability that the land has oil (event A)AND the test predicts that there is no oil (event B)" will be:

P(A and B) = P(A) * P(B)

Hence, the probability is 0.09 or 9%

User Danypata
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5.6k points