Question

Let N* be the total number of ranchers in Uruguay, and N(t) be the number of ranchers who have adopted an improved pasture technology there. Assume that the rate of adoption, , is proportional to both the number who have adopted the technology and the fraction of the ranchers who have not (and so are susceptible to conversion). Let a be the proportionality constant.

a. Write down the differential equation modeling N(t).
b. According to Banks (1993), N* = 17000, N(0) = 170, a = 0.5 per year.

Determine how long it takes for the improved pasture technology to spread to 80% of the population of the ranchers.

Answer 1

A) dN / dt = aN( N* - N ) /N*

B) 12 years

Explanation:

attached below is a detailed description of the solution

A) Write down the differential equation modelling N(t)

The differential equation of the modelling = dN / dt = aN( N* - N ) /N*

B) Determine how long it takes for improved pasture technology to spread to 80% of the population of the ranchers

firstly we will resolve the ODE and apply partial fractions, integrate and exponentiate before inputting the given data. attached below is a detailed solution