Mental Floss 291

The answer to last week’s challenge is. Q: There are three light switches in a room. You can do what you want with them and then go into the next room where there are three light bulbs. How can you identify the switch that turns on each of the lights? You can’t go back into the room with the switches. The wall between the rooms are sealed and the door locks behind you when you go into the second room.

A: In the first room, leave one of the light switches on for 10 mins and then turn it off. Leave one light switch on and the other off. In the second room then see which bulb is on, which one is off and which is warm from having been on.

This week’s lateral thinking challenge is.

Q: One tenant lives on the first floor of a 15 floor building. The number of tenants living on each successive floor is double that of the previous one. The building has a lift. Which button in the lift is the most worn?

The answer to this and a new challenge, next week …

Have an excellent weekend!

Share the Post

About the Author


No comment yet.


Your email address will not be published. Required fields are marked *