If I give my brother 5 dollars, then we will have the same amount of money. If instead he gives me 25 dollars, then I'll have twice as much money as he will have. How much money does my brother currently have (in dollars)?
Hello! The answer is $30.
We can form two equations with two variables based upon the given facts where x is the amount of money I have and y is the amount of money my brother has:
x5=y

x+25=2y

30 = y
Using system of equations, we find y = 30.
So your brother currently has 30 dollars.