Answer: There will 486 bacteria in 31 hours.
Step-by-step explanation:
The population decay in bacteria is exponential.
Exponential function : , where A = initial population, b multiplication decay factor, t= time:
As per given:
Initial population:
After 36 hours, population =
Divide both sides by 120,000 we get
Taking natural log on both sides , we get
At x= 31,
Hence, there will 486 bacteria in 31 hours.