Twice a fraction plus half that fraction, all times that fraction, equals the fraction. What is the fraction?
Let x be the fraction. First, we note that x = 0 is a solution. Now let’s look for a nonzero solution.
(2x + x/2) · x = x
2x + x/2 = 1
4x + x = 2
5x = 2
x = 2/5
2x + x/2 = 1
4x + x = 2
5x = 2
x = 2/5