SOLUTION: I am trying to work out this question, the number of bacteria is growing exponentially. if the number of bacteria rises from 100 to 350 in 6.5 hours ,how many bacteria will there b

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Question 737758: I am trying to work out this question, the number of bacteria is growing exponentially. if the number of bacteria rises from 100 to 350 in 6.5 hours ,how many bacteria will there be after 14 hours I don't now how to start of with this one please could you help
Answer by Susan-math(40) About Me  (Show Source):
You can put this solution on YOUR website!
f%28t%29=Ae%5E%28rt%29 where A=initial amount =100, t=number of hours and r=rate
so f%286.5%29=100e%5E%286.5r%29=350
this gives e%5E%286.5r%29=350%2F100=3.5
so ln%28e%5E%286.5r%29%29=ln%283.5%29
so 6.5r+=+ln%283.5%29
and r=ln%283.5%29%2F6.5=.193
Now to find out when t=14
f%2814%29=100e%5E%2814%2A%28.193%29%29=100e%5E%282.702%29=1490.952