### #1 - Probability Riddle Loaded Revolver

Henry has been caught stealing cattle, and is brought into town for justice. The judge is his ex-wife Gretchen, who wants to show him some sympathy, but the law clearly calls for two shots to be taken at Henry from close range. To make things a little better for Henry, Gretchen tells him she will place two bullets into a six-chambered revolver in successive order. She will spin the chamber, close it, and take one shot. If Henry is still alive, she will then either take another shot, or spin the chamber again before shooting.

Henry is a bit incredulous that his own ex-wife would carry out the punishment, and a bit sad that she was always such a rule follower. He steels himself as Gretchen loads the chambers, spins the revolver, and pulls the trigger. Whew! It was blank. Then Gretchen asks, 'Do you want me to pull the trigger again, or should I spin the chamber a second time before pulling the trigger?'

What should Henry choose?

Henry should have Gretchen pull the trigger again without spinning.

We know that the first chamber Gretchen fired was one of the four empty chambers. Since the bullets were placed in consecutive order, one of the empty chambers is followed by a bullet, and the other three empty chambers are followed by another empty chamber. So if Henry has Gretchen pull the trigger again, the probability that a bullet will be fired is 1/4.

If Gretchen spins the chamber again, the probability that she shoots Henry would be 2/6, or 1/3, since there are two possible bullets that would be in firing position out of the six possible chambers that would be in position.

### #2 - River Riddle

Four people need to cross a dark river at night.They have only one torch and the river is too risky to cross without the tourch. if all people cross simultanoesly then torch light wont be sufficient.Speed of each person of crossing the river is different.cross time for each person is 1 min, 2 mins, 7 mins and 10 mins. What is the shortest time needed for all four of them to cross the river ?

The initial solution most people will think of is to use the fastest person as an usher to guide everyone across. How long would that take? 10 + 1 + 7 + 1 + 2 = 21 mins. Is that it? No. That would make this question too simple even as a warm up question.

Let's brainstorm a little further. To reduce the amount of time, we should find a way for 10 and 7 to go together. If they cross together, then we need one of them to come back to get the others. That would not be ideal. How do we get around that? Maybe we can have 1 waiting on the other side to bring the torch back. Ahaa, we are getting closer. The fastest way to get 1 across and be back is to use 2 to usher 1 across. So let's put all this together.

1 and 2 go cross
2 comes back
7 and 10 go across
1 comes back
1 and 2 go across (done)

Total time = 2 + 2 + 10 + 1 + 2 = 17 mins

### #3 - Popular Liar Truth Riddle

Suarez is a strange liar.

He lies on six days of the week, but on the seventh day he always tells the truth.

He made the following statements on three successive days:

Day 1: "I lie on Monday and Tuesday."
Day 2: "Today, it"s Thursday, Saturday, or Sunday."
Day 3: "I lie on Wednesday and Friday."

On which day does Suarez tell the truth?

Tuesday

We know that Suarez tells the truth on only a single day of the week. If the statement on day 1 is untrue, this means that he tells the truth on Monday or Tuesday. If the statement on day 3 is untrue, this means that he tells the truth on Wednesday or Friday. Since Suarez tells the truth on only one day, these statements cannot both be untrue. So, exactly one of these statements must be true, and the statement on day 2 must be untrue.
Assume that the statement on day 1 is true. Then the statement on day 3 must be untrue, from which follows that Suarez tells the truth on Wednesday or Friday. So, day 1 is a Wednesday or a Friday. Therefore, day 2 is a Thursday or a Saturday. However, this would imply that the statement on day 2 is true, which is impossible. From this we can conclude that the statement on day 1 must be untrue.

This means that Suarez told the truth on day 3 and that this day is a Monday or a Tuesday. So day 2 is a Sunday or a Monday. Because the statement on day 2 must be untrue, we can conclude that day 2 is a Monday.

So day 3 is a Tuesday. Therefore, the day on which Suarez tells the truth is Tuesday.

### #4 - Tricky Murder Mystery Logical Riddle

Four boys were playing a game in which they need to throw three stone in the water so that the stone at don't get sunk into the water(there is some solid area in water).
Boy1: Succeeded in throwing 2 stones at solid area but 1 of the stone sunk.
Boy3: All stones got sunk.
Boy4: None of the stones got sunk.

Boy2 was the winner but was struck by a stone in the head and died.

Who killed Boy2 ?

Boy1, he was left with one stone.

### #5 - Trick Teaser Ias Interview Question

A Sweet girl purchased a book from a bookkeeper and give him Rs. 100.
The cost of book is Rs.30 but the bookkeeper had got no change, so he get the change from next shop and return the girl her 70 Rupees.

After some time time the next shopkeeper comes with the 100Rs note and told the bookkeeper that the note is fraud, so he takes money back.

How much loss did the bookkeeper face ?

100Rs

### #6 - Awesome Idea Puzzle Problem

Dwayne Johnson was running away with the loot from a heist in his car along with Vin Diesel. One tire was punctured and he dropped down to replace it. While changing the wheel, he dropped the four nuts that were holding the wheel and they fell into a drain. Vin Diesel gave him an idea using which they were able to drive till the rendezvous point.

What was the idea ?

Vin Diesel told him to use one nut from each of the other wheels.

### #7 - Measuring Time Interview Problem

I possess two wires. Both of them have an inconstant thickness but both of them burns completely in sixty minutes. The problem is that I want to measure forty-five minutes while using these two wires.

How can I measure if cutting the wire in half is not possible due to non-homogeneous construction ?

45minutes

It is not as hard as it seems. I will burn one wire on both ends and the other wire at one end only. The first wire will burn completely in thirty minutes and at that very moment, I will burn the other end of the second wire and it will burn in fifteen minutes. Thus both of the wires will be burnt in 30 + 15 = 45 minutes.

### #8 - Great Logic Riddle

Q1. Identify the first question where c) is the accurate answer
a) Q3
b) Q4
c) Q1
d) Q2

Q2. Identify the first question where a) is the accurate answer
a) Q4
b) Q2
c) Q3
d) Q1

Q3. Identify the first question where d) is the accurate answer
a) Q1
b) Q2
c) Q4
d) Q3

Q4. Identify the first question where b) is the accurate answer
a) Q2
b) Q4
c) Q3
d) Q1

D
C
A
B

### #9 - Aeroplane Hijack puzzle

A man hijacks an aeroplane transporting both passengers(8 of them) and valuable cargo. After taking the cargo, the man demands nine parachutes, puts one of them on, and jumps, leaving the other eight behind. Why did he want eight?

If the officials thought he was jumping with a hostage, they would never risk giving him a faulty parachute.

### #10 - Famous Elevator Puzzle

A man who lives on the tenth floor takes the elevator down to the first floor every morning and goes to work. In the evening, when he comes back; on a rainy day, or if there are other people in the elevator, he goes to his floor directly. Otherwise, he goes to the seventh floor and walks up three flights of stairs to his apartment.
Can you explain why?

The man is a of short stature. He can't reach the upper elevator buttons, but can push is with his umbrella.