Difficulty Popularity

There are 100 bulbs lined up in a room. All are turned on in the first pass. Then all the even numbered light bulbs are switched off. After that, every third bulb is switched on. Then all those bulbs that were switched off are turned back on and all those that were lit are turned off. Then the same process is being carried with the fourth bulb and the fifth bulb.

How many bulbs are glowing after 100 passes?

How many bulbs are glowing after 100 passes?

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Difficulty Popularity

Difficulty Popularity

We all know that New Year occurs after a week from Christmas and thus it falls on the same day as of Christmas. But this will not happen in 2050. In 2050, Christmas will appear on Sunday while New Year will appear on Saturday.

How can this be possible ?

How can this be possible ?

Difficulty Popularity

A barman is having a 12 liters jug full of beer. He needs to divide or split that beer into two equal parts. All he has is two empty jugs of capacity 8 liters and 5 liters.

How will he do it using them?

How will he do it using them?

Difficulty Popularity

Below rebus represents the current Temperature.

0

=========

B.Sc

LLB

What is the current Temperature ?
**category** :
REBUS

0

=========

B.Sc

LLB

What is the current Temperature ?

Difficulty Popularity

A wicked sorcerer felt enmity towards elf and thus he chooses four among the rest of the elf's and concealed them. The elves are concealed in the ground in a manner that apart from their head the rest of their body was underneath the ground. The elf's are unable to move their body and can only see in that direction that they are facing. All the elf's are concealed underground in such a way that they form a straight line and among those four elf's that are concealed underground one of the elf is detached form the other three elf's via wall. The entire elf's are in the same direction. The elf that is the furthest can only see the heads of its friends in front and a wall. The elf that is second last can only see one head of his friend and a wall. The second elf can only view the wall. The elf can see nothing.

The sorcerer understands the situation and tells the elf's that he has placed hats over their heads. Among the hats places two hat are blue and the other two are red. Among all the four elfs one of the elf has to guess that which colour hat is he wearing. If the elf answers correctly then he shall be set free or else he will have to dig beneath the ground till the very last.
**category** :
LOGIC

The sorcerer understands the situation and tells the elf's that he has placed hats over their heads. Among the hats places two hat are blue and the other two are red. Among all the four elfs one of the elf has to guess that which colour hat is he wearing. If the elf answers correctly then he shall be set free or else he will have to dig beneath the ground till the very last.

Difficulty Popularity

Difficulty Popularity

There are 100 doors. 100 strangers have been gathered in the adjacent room. The first one goes and opens every door. The second one goes and shuts down all the even numbered doors – second, fourth, sixth... and so on. The third one goes and reverses the current position of every third door (third, sixth, ninth… and so on.) i.e. if the door is open, he shuts it and if the door is shut, he switches opens it. All the 100 strangers progresses in the similar fashion.

After the last person has done what he wanted, which doors will be left open and which ones will be shut at the end?
**category** :
LOGIC

After the last person has done what he wanted, which doors will be left open and which ones will be shut at the end?

Difficulty Popularity

You had an infinite supply of water and a 5 ml and 3 ml gallons.

How would you measure exactly 4 ml in least number of steps ?

How would you measure exactly 4 ml in least number of steps ?

Difficulty Popularity

You live in Dubai and had an infinite supply of oil and a 5 liters and 3 liters jar,

how would you measure exactly 4 liters (of-course in minimum numbers of step) ?

how would you measure exactly 4 liters (of-course in minimum numbers of step) ?

Difficulty Popularity

If 1 + 9 + 11 = 1, Then what is the value of

12 + 11 + 9 = ?

12 + 11 + 9 = ?

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