How many bankers does it take to change a light bulb?
Four—one to hold the bulb and three to try to remember the combination.
Bankers and Light Bulbs
Explanation
Explain Bear
Listen up, tiny brain. Bankers spend their whole lives staring at vault combinations. This joke means they're so obsessed with security they think a light bulb needs a secret code. You probably can't even remember your own zip code, so focus.