SOLUTION: A biologist finds that the population of a certain type of bacteria doubles each half-hour. An initial culture has 90 bacteria. How long will it take for the number of bacteria to

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Question 388014: A biologist finds that the population of a certain type of bacteria doubles each half-hour. An initial culture has 90 bacteria.
How long will it take for the number of bacteria to reach 368,640?
Answer by Fombitz(32388) About Me  (Show Source):
You can put this solution on YOUR website!
368640=90%2A2%5E%28kt%29
where
180=90%2A2%5E%28k%2830%29%29
2=2%5E%2830k%29
30k=1
k=1%2F30
So then,
2%5E%28t%2F30%29=4096
2%5E%28t%2F30%29=2%5E12
t%2F30=12
highlight%28t=360%29minutes