The current birth rate per thousand is 32, whereas the corresponding death rate is 11 per thousand. The net growth rate in terms of population increase in percent is given by

### Concept & Logic This question involves converting **Rates per Thousand** into **Percentage Rates (per hundred)**. The net growth is the difference between births and deaths. The crucial step is understanding the base unit. "Per thousand" means out of every 1000 people. "Percent" means out of every 100 people. ### Step-by-step Solution * **Given:** * Birth rate = 32 per thousand * Death rate = 11 per thousand * **Calculation:** * First, find the net growth rate per thousand: $$\text{Net Growth per thousand} = \text{Birth rate} - \text{Death rate}$$ $$\text{Net Growth per thousand} = 32 - 11 = 21$$ * This means the population grows by 21 people for every 1000 people. * To find the percentage (per 100), we divide this rate by 10: $$\text{Net Growth Percent} = \frac{21}{1000} \times 100$$ $$\text{Net Growth Percent} = \frac{21}{10} = 2.1\%$$ ### Exam Strategy & Shortcut Understand the direct relationship between "per mille" (per thousand) and "per cent" (per hundred). Since $1000$ is ten times $100$, to convert a rate per thousand to a percent, simply divide by 10. Net rate = $32 - 11 = 21$. Percent = $\frac{21}{10} = 2.1\%$. ### Common Pitfall The trap here is the decimal placement. Students might see the net difference of 21 and hastily select option (d) 21% without converting "per thousand" to "percent". Always pay close attention to the units requested in the final question. ### Final Answer **Therefore, the correct answer is 2.1%.**