Question

A town's population is currently 2,183. If the population doubles every 28 years, what will the population be 140 years from now?

Answer 1

Answer:

=69805

Step-by-step explanation:

This is an exponential growth problem.  If the population doubles periodically, it follows a law like this:

P(t) = P(0)e^kt

where P(0) is the initial population at time t=0, and k is a constant with units of years-1.

To find k, let t=0.  Then P(t) = P(0) = initial population = 2183.

Since the population doubles every 28 years, we can write

P(t+28) = 2P(t)

P(0)ek(t+28) = 2[P(0)e^kt] 

Simplifying,

e²⁸k = 2

k = ln(2) / 28 = 0.02475 years-¹

Finally,

P(t) = 2183e⁰.⁰²⁴⁷⁵t, t in years

P(t)= 2183e^0.02475t, t in years

Then at t=140 years from now,

P(140) = 2183e⁰.⁰²⁴⁷⁵×¹⁴⁰

P(140) = 2183e^(0.02475 × 140) = 69804.61168

=69805