On a game show there are three closed doors – one hides a car and the other two conceal a goat. The contestant selects a door, which remains closed, and the host, knowing where the car is hidden, reveals a goat behind one of the remaining two doors. The contestant is then given the option to switch doors or stay with the one they originally selected. What should the contestant do to have the best chance of winning the car?
The contestant should switch doors, which doubles the chance of winning the car. Initially there is a 2/3 chance of picking a goat, but once the other goat is revealed, switching to remaining door gives the contestant a better chance of winning the car. This is known as the Monty Hall Problem and can be very unintuitive.
A man saw a snake crossing the road and swerved to crush it with his tires. All the street lights were off as well as the car’s headlights. There were no other lights on along the road.
You have 12 black socks and 12 white socks mixed up in a drawer. You’re up very early and it’s too dark to tell them apart. What’s the smallest number of socks you need to take out (blindly) to be sure of having a matching pair?
Three socks. If the first sock is black, the second one could be black, in which case you have a matching pair. If the second sock is white, the third sock will be either black and match the first sock, or white and match the second sock.
A strike in bowling is good. In baseball it’s good for the pitcher but not for the batter. You can strike a match to light it. When the clock strikes one a gong sounds and when you strike a paragraph, it’s gone.
Supposedly this is given as a test in Japan. I have no idea if that’s accurate.
There are 8 people who have to cross the river on a raft.
1. Policeman 2. Thief 3. Father 4. Boy 1 5. Boy 2 6. Mother 7. Girl 1 8. Girl 2
The rules are:
Only two people can cross at a time. Only the adults can operate the raft. The father can’t be with the girls unless the mother is there. The mother can’t be with the boys unless the father is there. The thief can’t remain with anyone unless the policeman is present.
How do you get them all across?
Instead of working it out by hand, here’s a flash version.
Click on the circle to start. Click on a person to put them on the raft and click on the lever to make the raft cross.
