Population growth

Run this example

# Exponential model for population growth

let initial_population = 50_000 people
let growth_rate = 2% per year

fn predict_population(t) =
    initial_population × e^(growth_rate·t) |> round_in(people)

print("Population in  20 years: {predict_population(20 years)}")
print("Population in 100 years: {predict_population(1 century)}")