Your question is Weighing Balls Logic Riddle. Take a moment with it on the right.
Talk me through your thinking if you like. When you're confident, submit your answer and I'll grade it like a real screen (7/10 or better passes).
Solve this logic riddle: You have 9 balls, equally big, equally heavy, except for one which is a little heavier. How would you identify the heavier ball if you could use a pair of balance scales only twice?