Sure about that?

Anna: Okay, I’ve put 100 balls in this urn. Some of them are red. I won’t give you any other info. How many red balls do you guess are in there?

Bella: 50

Camilla: 20

Anna: Good, now I’ll draw a ball out… Oh, it’s red! Let’s set it aside. Okay, what’s your guess now?

Bella: 49

Camilla: 40

Bella: What, a red ball was just removed, but now you’re claiming the number of red balls is higher than before?! Are you absolutely sure about that?

Camilla: No.