I am provided with an example for an Exponential mode, but I can't understand parts of it, I'd appreciate if some one could explain them a bit more.
There are apporximately ten times as many red kangaroos as grey kangatoos in a certain area. If the population of grey kangaroos increases at a rate of 11% per annum while that of the red kangaroos decreases at 5% per annum, find how many years must elapse before the proportions are reversed, assuming the same rates continue to apply.
Let = population of grey kangaroos at the start.
Therefore the number of grey kangaroos after years =
The number of red kangaroos after years =
Question 1 : Why is the percentage raised to the power of (+n years later)?
When Proportions are reversed:
Question 2 : Why is multiplied by ?