Question

The annual rate of growth in population of a certain city is 8%. If its present
population is 196830. What was population 3 years ago?​

Answer 1

Answer:

we know that

$a = p(1 + \frac{r}{100})^{n} \\ \\ 196830 = p( {1 + \frac{8}{100}) }^{3} \\ \\ 196830 = p( {1 + \frac{2}{25} )}^{3} \\ \\ 196830 = p( { \frac{27}{25}) }^{3} \\ \\ 196830 = \frac{19683}{15625}p \\ \\ 196830 \times \frac{15625}{19683} = p \\ \\ p = 156250$

therfore population before 3 years= 156250