Given:
The growth of a sample of bacteria can be modeled by the function

where, b is the number of bacteria and t is time in hours.
To find:
The number of total bacteria after 3 hours.
Solution:
We have,

where, b is the number of bacteria and t is time in hours.
Substituting t=3, we get the number of total bacteria after 3 hours.


Number of bacteria cannot be decimal value. So, approximate the value to the nearest whole number.

Therefore, the number of total bacteria after 3 hours is about 3003.