In a particular part of the Volta lake, there is a population of 100000 tilapia. The number of tilapia is decreasing at a rate of 10% per year due to pollution from a human settlement on the shores of the Volta lake in this area.
2. Copy and complete the table below to show the number of tilapia P after 1, 2 and 3 years
Number of years (t) 0 1 2 3
Number of tilapia (N)
Criterion B 1-2
b) Write an exponential model for the number of tilapia N after t years
Criterion B 3-4
c) When the population of tilapia falls below 25000 it is at a ‘critical level’. Write an inequality and calculate how long it will take for this lake to be at a critical level.