Answer:
Step-by-step explanation:
Let the initial population of country A represented by and the population of country B is represented by ,
Then, According to the question,
----------(1)
Since, the population of country A is increasing at a rate of 5% per year,
Hence, the population of A after x years
Similarly, the population of country B is increasing at a rate of 21.551 % per year,
Hence, the population of B after x years
Thus, the ratio of the population of A and that of B is,
By equation (1),
Which is the required function.