Two girls ate dinner together. They both ordered ice tea. One girl drank really fast and finished 5 in the time that took the other to drink just one. The girl who drank one died while the other survived. Both drinks were poisonous. How did the girl that drank the most survive?

“The girl who drank fast had a stronger immunity.”

This is incorrect because the riddle specifies that both drinks were poisonous. The immunity of the girl who drank quickly does not account for the poison present in the drinks.

“The girl who drank slowly was allergic to ice tea.”

This guess misunderstands the premise of the riddle. It states that both girls ordered ice tea, so the poison in the drink, not a reaction to the beverage itself, is the key element.

“The girl who drank fast accidentally drank a non-poisonous drink.”

This is wrong because the riddle explicitly states that both drinks were poisonous. There is no indication that one drink was safe, making this guess invalid.