Puzzles
The Triangle Puzzle
This simple puzzle that requires mid school math is quite entertaining. Can you figure out how do we get an empty square just by re-arranging the same pieces of the triangle ?
BTW Believe it or not, the picture below is not an animation.
As I was going to Saint Ives, I crossed the path of seven wives. Every wife had seven sacks, Every sack had seven cats, Every cat had seven kittens, Kittens, cats, sacks, wives, How many were going to Saint Ives?
Three people check into a hotel. They pay $30 to the manager, and go to their room. The manager finds out that the room rate is $25 and gives $5 to the bellboy to return. On the way to the room the bellboy reasons that $5 would be difficult to share among three people so he pockets $2 and gives $1 to each person. Now each person paid $10 and got back $1. So they paid $9 each, totaling $27. The bellboy has $2, totaling $29. Where is the remaining dollar?
Three people check into a hotel. They pay $30 to the manager, and go to their room. The manager finds out that the room rate is $25 and gives $5 to the bellboy to return. On the way to the room the bellboy reasons that $5 would be difficult to share among three people so he pockets $2 and gives $1 to each person. Now each person paid $10 and got back $1. So they paid $9 each, totaling $27. The bellboy has $2, totaling $29. Where is the remaining dollar?
There are 100 lions and 1 cow. Each lion can eat cow if he wants, but he will be transformed into cow also. Is the cow safe ?
You run a cross country race 10 km long in 50 minutes. Prove that there was a stretch of 2 km which you covered in exactly 10 minutes.
A person starts from Chandigarh at 6:00 am in the morning and reaches New Delhi at 11:00 am. The next day, that person starts from Delhi at 6:00 am exactly where he reached at 11:00 am yesterday, and reaches Chandigarh at 11:00 am, again exactly at the same point. Prove that there was a point between Chandigarh and Delhi where he was present at the same time on both the days.
A fair coin is tossed repeatedly until there is a run of an odd number of heads followed by a tail. Determine the expected number of tosses.
You are given a stream of numbers. You have to give a method by which you select from among them a number, such that the probability of choosing any no is equal. You have constant amount of memory i.e. cannot store all the numbers for choosing later.