Science:Math Exam Resources/Courses/MATH110/December 2014/Question 08 (c)
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Question 08 (c) 

Assume that the number of bacteria at time (in minutes) follows an exponential growth model , where and are constant. Suppose the count in the bacteria culture was 300 after 15 minutes and 1800 after 40 minutes. You may leave your answers unsimplified, i.e. in "calculatorready" form. (c) When will the culture contain 3000 bacteria? 
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Hint 

Find satisfying . 
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Solution 

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Please rate my easiness! It's quick and helps everyone guide their studies. Plug and obtained from part (a) into the expression of ;
Now, we solve ;
Therefore, we have 3000 bacteria in 