SOLUTION: The number of bacteria increased exponentially. At first there were 300. Six hours later there were 900. How many bacteria will there be in twelve hours? This is what I did, s

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Question 862226: The number of bacteria increased exponentially. At first there were 300. Six hours later there were 900. How many bacteria will there be in twelve hours?
This is what I did, solve for k? I got k= .18 by using this formula, 900=300e^k(6)
I am having trouble solving this. I get 2601 the solutions manual has 2700.
Answer by josgarithmetic(39620) About Me  (Show Source):
You can put this solution on YOUR website!
Your model is ... not bad. Try this: 900=300e%5E%28k%2A6%29.
Simplify and solve for k.
3=e%5E%28k%2A6%29
ln%283%29=ln%28e%5E%286k%29%29
ln%283%29=6k%2A1
highlight_green%28k=%281%2F6%29ln%283%29%29
highlight%28k=0.183%29

Now, let t=12 hours, and find the bacteria count.
C=300%2Ae%5E%280.183%2A12%29
C=300%2A9
highlight%28C=2700%29.

Notice that my solution simply used three significant figures while yours used two significant figures in the k value. That is why you found C=2601.