Suppose the population of a country in 1985 was 145 million. In 1995 it was 190 million. Use the formula P = Ae*
kt to setup an expression to estimate the population of the country in 2005.

Question

Suppose the population of a country in 1985 was 145 million. In 1995 it was 190 million. Use the formula P = Ae*
kt to setup an expression to estimate the population of the country in 2005.

campbell_st · Answer

is t the time in years since 1985..?

anonymous · Answer

i think so

campbell_st · Answer

ok... so that means your initial population A = 145

at t = 10 the P = 190

so your equation becomes 

$$190 = 145e^{10k}$$

you need to find the growth constant k

so 

$$\frac{190}{145} = e^{10k}$$

take the ln of both sides to find k

$$\ln(\frac{190}{145}) = 10k$$

when you know k... substitute it into the equation 

$$P = 145e^{kt}$$

to find the population in 2005... let t = 20.. 

hope that makes sense...

anonymous · Answer

yep thanks