Here is a puzzle suggested to me by one of the dads at the school soccer practice:
You have three cards: each has two colored sides.
One with both sides colored red.
Second with both sides green.
And a third with one side green and one red.
You close your eyes and pick one of the cards. You open your eyes and see that the side pointing to you is green. What are the chances of the back side of this card being red?
See TheMathMom presentation:
Popular Puzzles
-
This is an easy puzzle that you all are welcome to share with your kids and friends: Put addition signs between the digits 88888888 to get ...
-
This puzzle arrived via email from one of the fans. Can you move just one match to make this statement correct? There is more than one sol... -
Here is a number magic trick that came to me via mail. All of you, math detectives, are invited to unveil its magic with your logic. Tak... -
This came in a magic trick box that our daughter picked for her birthday. Exhausted from all the Bar Mitzvah preparations for her older b... -
This came from my son who got it from someone else at school. I solved it quickly and texted him the answer just as I was getting into ... -
Magic squares are tables of numbers where sums of every row, every column and both diagonals produce the same number. No, they were not in... -
My daughter's school teacher is showing kids some number mysticism. She told them to take any 3 digit number, e.g.793. Scramble its digi... -
We are done with the winter Olympics and now are looking forward to the Oscar's entertainment. As we saw in the previous puzzle , t... -
I found this puzzle in a tiny but mighty pocket puzzle book named Optical Illusions. Suppose the yellow billiard ball strikes the bumper a... -
You have 42 parrots and 7 cages of various sizes. Lock all the parrots inside the cages so that no cage is empty and each cage contains an ...
2 comments:
As i am seing a side with GREEN colour, so it can't be the card with both sides RED.
so it can be any one of GREEN-GREEN or GREEN-RED card. So in total there are 3 GREEN sides, so there are total 3 possibilities, out of which in one case the other side is RED. So the probability is 1/3
Regards
rakhel.parida@yahoo.com
Wow, Rakhel!
You seem to be a pro.
This was a tricky puzzle. Very similar to the "three doors" or Monty Hall puzzle that confused people for many many years.
Post a Comment
Note: Only a member of this blog may post a comment.