Math
posted by Leyla .
A culture contains 12,000 bacteria. After an hour the count is 25,000. Find the number of bacteria after 3 hours.

Math 
Reiny
let's assume the growth of bacteria is "almost" continuous
so number = initial value e^(kt) where k is a constant
so 12000 e^(1k) = 25000
e^k = 2.0833333...
k = ln 2.083333.. =.733969
number after 3 hrs = 12000 e^(3(.733969)) = 108506.9 or
109,000 to the nearest thousand
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