At time t = 0, a country's population is 300 million, and its death rate exceeds its birth rate by k. There is also a constant immigration of (I) million people each year. Which of these differential equations describes this situation?
I think its 300 e^-kt + (I)
What you have given is not the differential equation. I think you want
dp/dt = -kp + 1
But that is an exponential growth function, which is what your previous post was asking.