Aptitude Questions : Toughest Bulb Logic Interview Puzzle

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?

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Aptitude Questions : Spatial Trivia Physics Puzzle

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As shown in picture, there are four gears with the following specification
* Gear A has 60 teeth
* Gear B has 40 teeth
* Gear C has 20 teeth
* Gear D has 60 teeth
* Every minute, Gear B makes 15 complete turns.

What is the relative speed of Gear A and Gear B?

Aptitude Questions : Funny Brain Twister

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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 ?
category : LOGIC | TRICK

Aptitude Questions : Water Measurement Riddle

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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?
category : LOGIC | MEASURE

Aptitude Questions : Whats The Temperature Rebus

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Below rebus represents the current Temperature.

0
=========
B.Sc
LLB

What is the current Temperature ?
category : REBUS

Aptitude Questions : The Elf Logical Puzzle

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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

Aptitude Questions : Decipher MatchSticks Puzzle

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Can you decipher the two rows to find the hidden word?

Aptitude Questions : Hard Logic Brain Teaser

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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

Aptitude Questions : Measure Water Supply Brain Teaser

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 ?
category : LOGIC | MEASURE

Aptitude Questions : Famous Water Jug Problem

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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) ?
category : LOGIC | MEASURE

Aptitude Questions : Cool Equation Riddle

Difficulty Popularity

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

12 + 11 + 9 = ?

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