# Math Question

Discussion in 'DAT Discussions' started by Doogie Howser, Apr 29, 2007.

1. ### Doogie Howser practicing since age 12 5+ Year Member

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Say there is a minor disease A that affects on average 1 of 3 people. What are the chances of randomly selecting a group of 4 people and having 1 person affected?

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3. ### Lonely Sol cowgoesmoo fan! 10+ Year Member

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Well, you know 1/3 people is effected with the diseases and 2/3 people are not effected with the disease.

Since, there is 1 person effected out of 4, then:
1/3*(2/3)^3 = 8/81

4. ### Doogie Howser practicing since age 12 5+ Year Member

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oh duh, i don't know how i missed that

5. ### Lonely Sol cowgoesmoo fan! 10+ Year Member

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Is that the right answer, besides why are you even opening a DAT text? You should be out enjoying!!

6. ### Streetwolf Ultra Senior Member Dentist 7+ Year Member

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But any of the 4 of them can have it so you multiply by 4 and get 32/81.

7. ### JohnnyOU Slow like Honey 7+ Year Member

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