SOLUTION: A bacteria culture started with 7,500 bacteria and increased by 45% in the first two hours. a) Find an expression for the number of bacteria t hours after it was first observed.

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Question 953952: A bacteria culture started with 7,500 bacteria and increased by 45% in the first two hours.
a) Find an expression for the number of bacteria t hours after it was first observed.
b) Find the number of bacteria that will be present after 8 hours.
c) When will the population reach 25,000?
d) How long does it take the population to triple in size?
Answer by josgarithmetic(39621) About Me  (Show Source):
You can put this solution on YOUR website!
Growth Model, y=p%2Ae%5E%28kt%29.

The description helps for finding k.
ln%28y%29=ln%28p%29%2Bkt
kt=ln%28y%29-ln%28p%29
Allowing for two equivalent formulas:
highlight_green%28k=ln%28y%2Fp%29%2Ft%29 and highlight_green%28t=ln%28y%2Fp%29%2Fk%29

The description assigns p=7500 and y=7500%2B%280.45%29%2A7500 and t=2. Compute k from that and then do the rest of the questions.