Initially, two balls of the same shape and size have charges of +8 and-2. The balls are brought together, allowed to touch, and then separated.
When they are touched, the total charge is evenly distributed among the whole surface and they behaves as if it is a single piece. Net charge at this point is +8-2=6 C. When they are separated, each ball will have a charge of 6/2 = 3 C.
