Predict how many bacteria will be present after 17 hours, Round your answer to the nearest whole number

Question

A culture started with 2,000 bacteria. After 4 hours it grew to 2,600 bacteria. Predict how many bacteria will be present after 17 hours. Round your answer to the nearest whole number. (Note: When solving for K, round to four decimal places)

Answer 1

The exponential growth formula is

 

A = A₀e^rt

In this problem

A = 2600

A₀ = 2000

t = 4

r = ?

 

The growth after 4 hours is given, so

 

2600 = 2000e^r4

 

1.3 = e^r4

ln 1.3 = 4r

r = .0656

 

Now you can use that rate and the same equation to find the growth after 17 hours