Bags and Colored Balls

Bag A has 10 Red balls and Bag B has 10 Green balls.
Shuffle Bag A move three balls from A to B then shuffle Bag B move three balls from B to A.
Which bag is likely have more number of balls of other color.

Answer: The chances are same.
Think about how many red ball will move back to A.
If just one, then Bag A will have 2 green, Bag B will have 2 red,
If just two, then Bag A will have 1 green, Bag B will have 1 red,
If all three, A doesn't have green, b doesn't have red.