Answer:
The population of the bacteria after 40 hours is 254.
Step-by-step explanation:
The initial population is 40 and the population of bacteria doubles every 15 hours.
The population function is defined as

Where P₀ is initial population, b is exponential growth rate.
Since the population of bacteria doubles every 15 hours, therefore the growth rate is



We have to find the population of the bacteria after 40 hours, so put
in the above equation.




Therefore the population of the bacteria after 40 hours is 254.