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You are provided with twenty five different horses and you must find out who are the fastest horses. You can conduct a race of five horses only at one time. There is no point in the race where you can find out the actual speed of a horse in a race.

How many races will it take to help you determine the fastest three horses?

How many races will it take to help you determine the fastest three horses?

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You are given with two ropes with variable width. However if we start burning both the ropes, they will burn at exactly same time i.e. an hour. The ropes are non-homogeneous in nature. You are asked to measure 45 minutes by using these two ropes.

How can you do it?

Please note that you can’t break the rope in half as it is being clearly stated that the ropes are non-homogeneous in nature.

How can you do it?

Please note that you can’t break the rope in half as it is being clearly stated that the ropes are non-homogeneous in nature.

Difficulty Popularity

A claustrophobic person boards a train that is just about to enter a tunnel.

Which place will be the best for him to sit?

Which place will be the best for him to sit?

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You have been given three jars of 3 liters, 5 liters and 8 liters capacity out of which the 8 liters jar is filled completely with water. Now you have to use these three jars to divide the water into two parts of 4 liters each.

How can you do it making the least amount of transfers?
**category** :
LOGIC

How can you do it making the least amount of transfers?

Difficulty Popularity

It takes ten minutes to fry a steak (five minutes for each side). You are frying the steaks in a pan that can accommodate only two steaks at one time. What is the least amount of time by which you can fry all the three steaks you have?

Difficulty Popularity

There is a box full of fruits,

all but two are grapes,

all but two are apples,

and all but two are oranges.

How many fruits are in the box ?

all but two are grapes,

all but two are apples,

and all but two are oranges.

How many fruits are in the box ?

Difficulty Popularity

There stand nine temples in a row in a holy place. All the nine temples have 100 steps climb. A fellow devotee comes to visit the temples. He drops a Re. 1 coin while climbing each of the 100 steps up. Then he offers half of the money he has in his pocket to the god. After that, he again drops Re. 1 coin while climbing down each of the 100 steps of the temple.

If he repeats the same process at each temple, he is left with no money after climbing down the ninth temple. Can you find out the total money he had with him initially?

If he repeats the same process at each temple, he is left with no money after climbing down the ninth temple. Can you find out the total money he had with him initially?

Difficulty Popularity

Three college toppers are summoned by the inspecting faculty. To identify the best from them, the faculty takes them into a room and places one hat on each of their heads. Now all of them can see the hats on other’s heads but can’t see his own. There are two colored hats – green and red.

Now the faculty announces that he had made sure that the competition is extremely fair to all three of them. He also gives them a hint that at least one of them is wearing a red hat. Now the first one who is able to deduce his own hat color will be awarded the most intelligent student of all award. After a few minutes, one of them raises his hand and is able to deduce the color correctly.

How?
**category** :
LOGIC

Now the faculty announces that he had made sure that the competition is extremely fair to all three of them. He also gives them a hint that at least one of them is wearing a red hat. Now the first one who is able to deduce his own hat color will be awarded the most intelligent student of all award. After a few minutes, one of them raises his hand and is able to deduce the color correctly.

How?

Difficulty Popularity

I can prove why 1 = 2

Step1. Lets say y = x

Step2. Multiply through by x xy = x2

Step3. Subtract y2 from each side xy - y2 = x2 - y2

Step4. Factor each side y(x-y) = (x+y)(x-y)

Step5. Divide both sides by (x-y) y = x+y

Step6. Divide both sides by y y/y = x/y + y/y

Step7. And so... 1 = x/y + 1

Step8. Since x=y, x/y = 1 1 = 1 + 1

Step9. And so... 1 = 2

How is this possible ?

Step1. Lets say y = x

Step2. Multiply through by x xy = x2

Step3. Subtract y2 from each side xy - y2 = x2 - y2

Step4. Factor each side y(x-y) = (x+y)(x-y)

Step5. Divide both sides by (x-y) y = x+y

Step6. Divide both sides by y y/y = x/y + y/y

Step7. And so... 1 = x/y + 1

Step8. Since x=y, x/y = 1 1 = 1 + 1

Step9. And so... 1 = 2

How is this possible ?

Difficulty Popularity

You are given a set of scales and 12 marbles. The scales are of the old balance variety. That is, a small dish hangs from each end of a rod that is balanced in the middle. The device enables you to conclude either that the contents of the dishes weigh the same or that the dish that falls lower has heavier contents than the other.

The 12 marbles appear to be identical. In fact, 11 of them are identical, and one is of a different weight. Your task is to identify the unusual marble and discard it. You are allowed to use the scales three times if you wish, but no more.

Note that the unusual marble may be heavier or lighter than the others. You are asked to both identify it and determine whether it is heavy or light.
**category** :
LOGIC

The 12 marbles appear to be identical. In fact, 11 of them are identical, and one is of a different weight. Your task is to identify the unusual marble and discard it. You are allowed to use the scales three times if you wish, but no more.

Note that the unusual marble may be heavier or lighter than the others. You are asked to both identify it and determine whether it is heavy or light.

Difficulty Popularity

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