Question

75,000 live bacteria are present in a culture in a flask. When an antibiotic is

added to the culture, the number of live bacteria is reduced as shown by the
equation. Approximately how many hours have passed when there are 4500
bacteria left alive?
4500 = 75,000 e-0.1733t

Answer 1

16.23 hours

Explanation:

To obtain the number of hours that have passed ; we have to solve for t on the equation ;

4500 = 75,000 e^-0.1733t

Divide both sides by 75000

4500/75000 = e^-0.1733t

0.06 = e^-0.1733t

Take the In of both sides ;

In(0.06) = - 0.1733t

-2.813410 = - 0.1733t

Divide both sides by - 0.1733

t = 16.23 hours