Let's break this down step by step:

First, let's simplify the expression within the square brackets: (2x-98)/2 + 56.

To simplify (2x-98)/2, we divide each term by 2:

(2x-98)/2 = x - 49

Now we add 56 to x - 49:

x - 49 + 56 = x + 7

Next, multiply the result by 36:

(x + 7) × 36 = 36x + 252

Now subtract 268 from the previous result:

36x + 252 - 268 = 36x - 16

Finally, divide the result by 500:

(36x - 16) ÷ 500 = (36x)/500 - 16/500 = 0.072x - 0.032

Therefore, the simplified expression is 0.072x - 0.032.