There are two numbers such that , if both of them are individually increased by 5 and then by the same percentage as they were increased in the first instance each would result in 36. find the difference between the two numbers

Let the two numbers be x and y.
Let m =  the fraction (or percentage) for increasing the numbers.
 
Increase x by 5, multiply (x+5) by (1+m), and set it qual to 36.
(x + 5)*(1 + m) = 36

Increase y by 5, multiply (y+5) by (1+m), and set it equal to 36.
(y+5)*(1+m) = 36

Therefore
(x+5)*(1+m) = (y+5)*(1+m)
x + 5 = y + 5
x = y
x - y = 0

0.
The difference between the two numbers is zero.