This riddle looks like a simple multiplication question, but the first sentence contains the real clue.
A woman buys a rooster, and the puzzle says it lays 3 eggs every day. How many eggs are there after 7 days?
The answer is 0.
Roosters are male chickens, so they do not lay eggs. That means there are no eggs to multiply by seven, no matter how convincing the rest of the wording sounds.
The trap is that many people immediately calculate 3 × 7 and answer 21 without checking whether the situation itself makes sense.
Answer: 0 eggs.
This is one of those riddles where careful reading matters more than arithmetic. The math is easy — the trick is noticing that a rooster cannot lay eggs in the first place.
