The population in millions of a certain country can be approximated by the function
P(x)=40 x 1.02^x
Where x is the number of years after 2000. Which of the following calculations will tell in what year the population can be expected to reach 200 million?
1. In(5)/In(1.02)
2. In(5/1.02)
3. In(5/1.02)+2000

Question

The population in millions of a certain country can be approximated by the function 
P(x)=40 x 1.02^x
Where x is the number of years after 2000. Which of the following calculations will tell in what year the population can be expected to reach 200 million?
1. In(5)/In(1.02)
2. In(5/1.02)
3. In(5/1.02)+2000

lilmike234 · Answer

Or In(5)/In(1.02)+2000

anonymous · Answer

200 = 40 * 1.02^x
200/40 = 1.02^x
5 = 1.02^x
ln(5) = ln( 1.02^x)
ln(5)= x * ln(1.02)
ln(5)/ ln(1.02) = x 

Did you get this far?

lilmike234 · Answer

Yeah and then I got stuck after this