# Functions

• Sep 17th 2008, 02:14 PM
asweet1
Functions
In 2006, the population of a country was 50 million and growing at the rate of 1.8% per year. Assuming the percentage growth rate remains constant, express the population, P (in millions), as a function of t, the number of years after 2006.
• Sep 17th 2008, 02:24 PM
Soroban
Hello, asweet1!

Quote:

In 2006, the population of a country was 50 million and growing at the rate of 1.8% per year.
Assuming the percentage growth rate remains constant, express the population, $P$ (in millions),
as a function of $t$, the number of years after 2006.

If the population increases at a rate of 1.8% per year,
. . each year's population is 1.018 times the previous year's population.
This is identical to a compound interest problem.

The function is: . $P(t) \;=\;50(1.018)^t$