Although there are many ways to use money, the equation can be used to multiply it.
Here it is:
1 -> (3×5)=15
By putting in a dollar, one can multiply it by 3×5 and it will equal $15. The 3 stands for population or people. The 5 is a dollar amount. Both can also stand for other thing as well. By increasing the original amount, it can be multiplied.