Question

The population of a city has been increasing at 5% every year. The present population is 185220. What was its population 3 years back?

• A. 180500
• B. 160000
• C. 180000
• D. 178000

Answer 1

Answer:

B. 160000

Let the population 3 years ago be x,

$x \times (105/100) ^ 3$ = $185220$

$x = 185220 * (20/21) ^ 3$

$x = 160000$