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Epidemic [need explanation]

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Epidemic [need explanation]

by snehit » Mon Jul 27, 2009 6:56 am
An epidemic is reported to have broken out in FL. The number of detected instances of a certain disease is reported to have increased by 85% in the last year. What is the lowest number of newly detected instances possible?

A 1

B 5

C 11

D 15

E 17

Source: Some harvard program
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by truplayer256 » Mon Jul 27, 2009 7:10 am
The number of newly detected instances possible when set to .85 multiplied by the previous number number of detected instances must create an integer x when divided by .85.

Let x= the previous number of detected instances.

A.) .85*x=1
x doesn't equal an integer so no.

B.) .85*x= 5. No

C.) .85*x= 11. No

D.) .85*x=15. No.

E.) .85*x=17. Yes, x=20.

E is our answer.
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by ghacker » Mon Jul 27, 2009 1:33 pm
Number of cases infected must be an integer ( assuming that we can divide the cases only in to two parts , those who have got it and those who have not got it )

So it must be a multiple of 0.85 , hence the answer is 17
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