Simple Explanation
Area unchanged होने पर population और density directly proportional हैं। Density increase \(100 - 80 = 20\) है। Percentage increase \(\frac{20}{80} \times 100 = 25\%\) है। इसलिए population भी 25 percent बढ़ी और दूसरा विकल्प सही है। परीक्षा में fixed area के कारण density percentage change को population percentage change के बराबर माना जा सकता है। / When area remains unchanged, population and density are directly proportional. Density rises by \(100 - 80 = 20\). The percentage increase is \(\frac{20}{80} \times 100 = 25\%\). Therefore, population also increased by 25 percent, making the second option correct. In examinations, with fixed area, the percentage change in density equals the percentage change in population.
