At first glance, all three eggs in this puzzle appear identical, but placing them in a glass of water reveals an important difference. 🥚 The question is: which egg would you be most cautious about eating? The clue lies in what happens inside an egg as it gets older.

A fresh egg typically sinks to the bottom and lies flat, like Egg 1. Egg 2 also sinks but stands more upright, which generally indicates that it is older because the air pocket inside the shell has become larger. Egg 3 floats near the surface, suggesting that it is the oldest of the three. As eggs age, moisture escapes through tiny pores in the shell, causing the internal air cell to expand and making the egg more buoyant.

That means Egg 3 is the likely answer if the puzzle is asking which egg is “bad.” However, there is an important detail to remember: a floating egg is not automatically spoiled or unsafe to eat. The water test can provide an indication of an egg’s age, but it cannot confirm whether harmful bacteria are present.

If you are unsure about an older egg, crack it into a separate bowl and check its appearance and smell before using it. A strong rotten or sulfur-like odor is a clear warning that it should be discarded. So, for this puzzle, the answer is Egg 3 because it has the largest air pocket and is the oldest. But floating indicates age, not definite spoilage. Did you choose Egg 3?