Because the actual population changes frequently.
Chat with our AI personalities
There are two types of significant figures, measured and exact. Numbers are often rounded to avoid reporting insignificant figures. Numbers can also be rounded merely for simplicity rather than to indicate a given precision of measurement.
3.1428
6.937
There is no sampling method that will select the exact population.
Any number between 250 and 350 - including 250, but not including 350 (depending on the exact rules used, actually).