The apartment building where Herman lives was built 12 years before his grandmother's house. In 4 years, the apartment building will be twice as many years old as Herman's grandmother's house. How many years ago was Herman's grandmother's house built?
To solve this problem, we need to create an equation using the information given. Let's assume the number of years ago Herman's grandmother's house was built is 'x' years.
According to the problem, the apartment building was built 12 years before the grandmother's house, so the apartment building is (x + 12) years old.
In 4 years, the apartment building will be twice as many years old as Herman's grandmother's house will be, so we add 4 years to each and set up the equation:
(x + 12 + 4) = 2(x + 4)
Now, we can solve this equation to find the value of 'x':
x + 16 = 2x + 8
By subtracting 'x' from both sides and simplifying, we get:
16 = x + 8
Subtracting 8 from both sides gives us:
8 = x
Therefore, Herman's grandmother's house was built 8 years ago.
If grandma's house = x, then the apartment building = x + 12
x + 12 + 4 = 2(x+4)
Solve for x.