In a school, the ratio of soccer players to volleyball players is 4 : 1. The number of soccer players is how many times the number of volleyball players?

Your question appears to be phrased incorrectly. If the ratio of soccer players to football players is 4:1 then for every 1 football player there are 4 soccer players. For example, if there are 3 football players, there would be 12 soccer players.

The equivalent expression would be S = 4F

The statement: "there are 4 more soccer players than football players" is not the same thing. It simply means that we add 4 to the total of football players to find out how many soccer players there are.

The equivalent expression would be S = F + 4

That being said: An equivalent ratio to 4:1 would be 8:2, 12:3, 16:4, ...

Think of the ratio as a fraction. 4:1 = 4/1

4/1 = 8/2 = 12/3 = 16/4 ..., etc.