Question

The population

decreasing
of a country town is
at a rate of 4% p.a.
How many years will it take for the town's
population of 15000 to fall below 10000?

Answer 1

Population after 2 years = P (1 + 4/100)2 = 62500 X (104/100)2

= 62500 × 26/25 X 26/25 = 100 × 26 ×26 = 67600.

Hence, the population after two years will be 67,600.

Answer 2

The rate of decrement is given as: r = 4%. From the table, the initial population is. P (0) = 7900. So, the population in t years is. P (t) = P (0) * (1 - r)^t. This gives. P (t) = 7900 * (1 - 4%)^t. Evaluate the difference.