Question

The number of bacteria in a certain population increases according to a continuous exponential growth model, with a growth rate parameter of 1.5% per hour. How many hours does it take for the size of the sample to double

Answer 1

It will take 47 hours

Explanation:

We can have the exponential function as follows;

P = I( 1 + r)^n

if the initial value was x , the final will be 2x

The change rate is 1.5% , which is r, this is same as;

1.5/100 = 0.015

So what we want to calculate is the n attached

This will be;

2x = x ( 1 + 0.015)^n

2 = 1.015^n

ln 2 = n ln 1.015

n = ln 2/ln 1.015

n = 46.55

This is approximately 47 hours