Write a real world problem that could represented by the following
30+0.05x=40+0.01x

In this item, we are given with two expressions that are equated to each other.

A real life scenario is that there are two items in the store, one item, we name it as Item A, is initially sold at a price of $30. The other item, Item B, is initially sold at $40. Let's say that for every interested buyer of Item A, the price increases by $0.05. Also, for every interested buyer of Item B, the price increases by $0.01. Then, we find how many interested buyer should be there for each of the item for the Items to have the same price. 

If we calculate the equation,
  30 + 0.05x = 40 + 0.01x
Transpose the like terms to one side of the equation and the constants to another.
   0.04x = 10
      x = 250