זה מזכיר לי את הבדיחה
The physicist and the engineer are in a hot-air balloon. Soon, they find themselves lost in a canyon somewhere. They yell out for help: "Helllloooooo! Where are we?" 15 minutes later, they hear an echoing voice: "Helllloooooo! You're in a hot-air balloon!!" The physicist says, "That must have been a mathematician." The engineer asks, "Why do you say that?" The physicist replied: "The answer was absolutely correct, and it was utterly useless."