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.

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
Respond to this Question
Similar Questions

precalculus
A bacteria culture initially contains 1500 bacteria and doubles every half hour. a) Find an expression for the number of bacteria after t hours. Q(t)= b) The number of bacteria after 20 minutes is (the answer must be an integer) c) … 
Calc
The number of bacteria in a culture is increasing according to the law of exponential growth. There are 125 bacteria in the culture after 2 hours and 350 bacteria after 4 hours. a) Find the initial population. b) Write an exponential … 
MATH :)
3. In Biology, it is found that the bacteria in a certain culture double every halfhour. If the initial number of bacteria in culture is 1000, A. Find the defining equation for the number N of bacteria in culture after T hours, assuming … 
Algebra 2
If there are initially 1500 bacteria in a culture, and the number of bacteria double each hour, the number of bacteria after t hours can be found using the formula N=1500(2^t). How many bacteria will present after 7 hours? 
calculus
2. The rate of change in the number of bacteria in a culture is proportional to the number present. In a certain laboratory experiment, a culture has 10,000 bacterial initially, 20,000 bacteria at time t1 minutes, and 100,000 bacteria … 
PreCalc/Trig...
is this the correct formula for me to solve this? 
Urgent math
population growth model. Can anybody please help me out in trying to solve this problem? 
Urgent math
The initial size of a culture of bacteria is 1000. After one hour the bacteria count is 4000. (a) Find a function n(t) = n0ert that models the population after t hours. n(t) = b)Find the population after 1.5 hours. (Round your answer … 
math
A culture starts with 8300 bacteria. After one hour the count is 10,000. (a) Find a function that models the number of bacteria n(t) after t hours. (Round your r value to three decimal places.) 
PreCalc
The initial size of a culture of bacteria is 1500. After 1 hour the bacteria count is 12000. (a) Find a function n(t) = n0e^rt that models the population after t hours. (Round your r value to five decimal places.) n(t) = (b) Find the …