**Mind Benders Puzzles 1 : 2 Eggs 100 Floors Puzzle**
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Difficulty ★★★★★
Popularity ★★★★★
-> You are given 2 eggs.

-> You have access to a 100-storey building.

-> Eggs can be very hard or very fragile means it may break if dropped from the first floor or may not even break if dropped from 100 th floor.Both eggs are identical.

-> You need to figure out the highest floor of a 100-storey building an egg can be dropped without breaking.

-> Now the question is how many drops you need to make. You are allowed to break 2 eggs in the process

Answer & Explanation

**Solution:**

answer is: 14

Let x be the answer we want, the number of drops required.

So if the first egg breaks maximum we can have x-1 drops and so we must always put the first egg from height x. So we have determined that for a given x we must drop the first ball from x height. And now if the first drop of the first egg doesnÃ¢€™t breaks we can have x-2 drops for the second egg if the first egg breaks in the second drop.

Taking an example, lets say 16 is my answer. That I need 16 drops to find out the answer. Lets see whether we can find out the height in 16 drops. First we drop from height 16,and if it breaks we try all floors from 1 to 15.If the egg don't break then we have left 15 drops, so we will drop it from 16+15+1 =32nd floor. The reason being if it breaks at 32nd floor we can try all the floors from 17 to 31 in 14 drops (total of 16 drops). Now if it did not break then we have left 13 drops. and we can figure out whether we can find out whether we can figure out the floor in 16 drops.

Lets take the case with 16 as the answer

1 + 15 16 if breaks at 16 checks from 1 to 15 in 15 drops

1 + 14 31 if breaks at 31 checks from 17 to 30 in 14 drops

1 + 13 45 .....

1 + 12 58

1 + 11 70

1 + 10 81

1 + 9 91

1 + 8 100 We can easily do in the end as we have enough drops to accomplish the task

Now finding out the optimal one we can see that we could have done it in either 15 or 14 drops only but how can we find the optimal one. From the above table we can see that the optimal one will be needing 0 linear trials in the last step.

So we could write it as

(1+p) + (1+(p-1))+ (1+(p-2)) + .........+ (1+0) >= 100.

Let 1+p=q which is the answer we are looking for

q (q+1)/2 >=100

Solving for 100 you get q=14.

So the answer is: 14

Drop first orb from floors 14, 27, 39, 50, 60, 69, 77, 84, 90, 95, 99, 100... (i.e. move up 14 then 13, then 12 floors, etc) until it breaks (or doesn't at 100)

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**Mind Benders Puzzles 2 : Aeroplane Hardest Quiz**
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Difficulty ★★★★★
Popularity ★★★☆☆
The puzzle question is : On Bagshot Island, there is an airport. The airport is the homebase of an unlimited number of identical airplanes. Each airplane has a fuel capacity to allow it to fly exactly 1/2 way around the world, along a great circle. The planes have the ability to refuel in flight without loss of speed or spillage of fuel. Though the fuel is unlimited, the island is the only source of fuel.

What is the fewest number of aircraft necessary to get one plane all the way around the world assuming that all of the aircraft must return safely to the airport? How did you get to your answer?

Notes:

(a) Each airplane must depart and return to the same airport, and that is the only airport they can land and refuel on ground.

(b) Each airplane must have enough fuel to return to airport.

(c) The time and fuel consumption of refueling can be ignored. (so we can also assume that one airplane can refuel more than one airplanes in air at the same time.)

(d) The amount of fuel airplanes carrying can be zero as long as the other airplane is refueling these airplanes. What is the fewest number of airplanes and number of tanks of fuel needed to accomplish this work? (we only need airplane to go around the world)

Answer & Explanation

**Solution:**

As per the puzzle given ablove The fewest number of aircraft is 3! Imagine 3 aircraft (A, B and C). A is going to fly round the world. All three aircraft start at the same time in the same direction. After 1/6 of the circumference, B passes 1/3 of its fuel to C and returns home, where it is refuelled and starts immediately again to follow A and C.

C continues to fly alongside A until they are 1/4 of the distance around the world. At this point C completely fills the tank of A which is now able to fly to a point 3/4 of the way around the world. C has now only 1/3 of its full fuel capacity left, not enough to get back to the home base. But the first 'auxiliary' aircraft reaches it in time in order to refuel it, and both 'auxiliary' aircraft are the able to return safely to the home base.

Now in the same manner as before both B and C fully refuelled fly towards A. Again B refuels C and returns home to be refuelled. C reaches A at the point where it has flown 3/4 around the world. All 3 aircraft can safely return to the home base, if the refuelling process is applied analogously as for the first phase of the flight.

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**Mind Benders Puzzles 3 : Sherlock Holmes Puzzle**
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Difficulty ★★★★★
Popularity ★★★☆☆
Sherlock Detective reviewed the information they had on the case so far.

A lady named 'himanshi' was found shot and they already had a list of suspects - Ankit , Tarun, Harish, Manoj and Manish.

Killer is a fan of sherlock and chalenge him by leaving notes ad various places.

* The first was found in a toilet room.

* The second was found in an art room.

* The third was in a restroom.

* the fourth in an underwater room.

* The fifth at the no smoking room.

All of the notes read the same thing, 'The clues are where you find the notes.' Yet, nothing was found at anyplace the notes were.

Sherlock the genius , immediately solved the case.

Who was the killer ?

Answer & Explanation

**Solution:**

Its Tarun

toilet room(T) , art room(a) , rest room (r) , underwater room (u) , no smoking room (n)

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**Mind Benders Puzzles 4 : Missing Piece Puzzle**
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Difficulty ★★★★☆
Popularity ★★★☆☆
Below the four parts have been reorganized. The four partitions are exactly the same in both arrangements. Why is there a hole?

Answer & Explanation

**Solution:**

he gradient of the teal hypotenuse is different than the gradient of the red hypotenuse.

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**Mind Benders Puzzles 5 : Science Murder Riddle**
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Difficulty ★★★★☆
Popularity ★★★☆☆
A man was going to bleach his socks because they had gotten muddy the day before. As he was pouring the bleach into the washing machine, he spilled some on the floor. He got some cleaning fluid and mopped it up with a rag. Minutes later he was dead. What killed him?

Answer & Explanation

**Solution:**

When you mix bleach and ammonia [found in most cleaning products] it creates a deadly gas that can kill.

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**Mind Benders Puzzles 6 : Toughest Series Puzzle**
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Difficulty ★★★★★
Popularity ★★★☆☆
What is the next number in this series?

4,12,84,3612....

Answer & Explanation

**Solution:**

6526884. To get from 4 to 12, you use the following formula. 12 = (4 squared)/2 + 4.

Continue on with (X^2)/2 + X.

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**Mind Benders Puzzles 7 : Decode This Message**
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Difficulty ★★★★★
Popularity ★★★★☆
Decode The Message

carrot fiasco nephew spring rabbit

sonata tailor bureau legacy corona

travel bikini object happen soften

picnic option waited effigy adverb

report accuse animal shriek esteem

oyster

Answer & Explanation

**Solution:**

Starting with the first two words, Take the first and last letters, reading from left to right. Example: Carrot fiascO "from these pairs" the message is as follows:

CONGRATULATIONS CODE BREAKER

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**Mind Benders Puzzles 8 : Hard Photo Puzzle**
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Difficulty ★★★★★
Popularity ★★★☆☆
What is the word or phrase??

Answer & Explanation

**Solution:**

Stand up and be counted

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**Mind Benders Puzzles 9 : Dream Riddle**
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Difficulty ★★★★★
Popularity ★★★☆☆
Two brothers were watching a horror film on video late one night. One brother dozed off and dreamed that he was being chased by the crazy man from the movie, who was trying to kill him. In the dream, he hid in a cupboard. There was no sound except his heart pounding, and he had no idea where his crazed captor was. He was terrified! At that moment, the video finished, and his brother put his hand on the shoulder of his sleeping sibling to wake him. The shock at that tense moment was enough that the sleeping brother suffered a massive heart attack and died instantly. True or false?

Answer & Explanation

**Solution:**

False- if he had instantly died, how would anybody know his dream

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**Mind Benders Puzzles 10 : Chess Puzzle**
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Difficulty ★★★★☆
Popularity ★★★☆☆
How many squares, of any size, can you find on this chess board which do not contain a Rook?

Answer & Explanation

**Solution:**

128.

There are 62 squares of size 1x1.

There are 41 squares of size 2x2.

There are 18 squares of size 3x3.

There are 6 squares of size 4x4.

There is 1 square of size 5x5.

A total of 62 + 41 + 18 + 6 + 1 = 128.

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