Final answer:
The mathematical expression representing four times as many soccer fans as football fans is x = 4y. Calculating subpopulations, such as the percentage of women who prefer football, involves dividing the number of women in the group by the total number of fans, which in one example is 5/25, yielding 0.2 or 20%.
Step-by-step explanation:
The relationship between the number of soccer fans (x) and football fans (y) can be described using a simple algebraic expression based on the information provided which is that there are four times as many soccer fans as football fans. This relationship is expressed as x = 4y.
To understand the concept of fandom and subpopulations within sports fans, consider a scenario where we have information on the number of women who prefer football. As described, if there are 5 women who prefer football out of a total football fan population of 25, then the subpopulation ratio is calculated as 5/25, which simplifies to 0.2 or 20%.
Such demographic breakdowns in fandom are quite informative as they reveal preferences and trends within sports enthusiasts. This analysis applies not only to football but also to other increasing sports like soccer where similar calculations could be used to understand the distribution of fans across different demographics and regions, following patterns of fandom.