problem3

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problem3

by Captchar » Fri Dec 21, 2012 10:15 am
A certain culture of bacteria quadruples every hour. If a container with these bacteria was half full at 10:00 a.m., at what time was it one-eighth full?

(A) 9:00 a.m.
(B) 7:00 a.m.
(C) 6:00 a.m.
(D) 4:00 a.m.
(E) 2:00 a.m.

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by Anurag@Gurome » Fri Dec 21, 2012 10:18 am
Captchar wrote:A certain culture of bacteria quadruples every hour. If a container with these bacteria was half full at 10:00 a.m., at what time was it one-eighth full?
4*(1/8) = 1/2

As the culture of bacteria quadruples every hour, in one hour it will grow from 1/8 full to half full.

Hence, it was 1/8 full at 9:00 AM.

The correct answer is A.
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