#181 - Find The Next Number

What are the next three numbers in this series?

4, 6, 12, 18, 30, 42, 60, 72, 102, 108, ?, ?, ?

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The series lists numbers that are flanked by two prime numbers.

4 (3 and 5 are prime)
6 (5 and 7 are prime)
12 (11 and 13 are prime)
18 (17 and 19 are prime)
30 (29 and 31 are prime)
42 (41 and 43 are prime)
60 (59 and 61 are prime)
72 (71 and 73 are prime)
102 (101 and 103 are prime)
108 (107 and 109 are prime)

thus

138 (137 and 139 are prime), 150 (149 and 151 are prime), 180 (179 and 181 are prime

#182 - Famous Probability puzzle SHOOT

Mr. Black, Mr. Gray, and Mr. White are fighting in a truel. They each get a gun and take turns shooting at each other until only one person is left. Mr. Black, who hits his shot 1/3 of the time, gets to shoot first. Mr. Gray, who hits his shot 2/3 of the time, gets to shoot next, assuming he is still alive. Mr. White, who hits his shot all the time, shoots next, assuming he is also alive. The cycle repeats. If you are Mr. Black, where should you shoot first for the highest chance of survival?

Famous Probability puzzle SHOOT
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He should shoot at the ground.

If Mr. Black shoots the ground, it is Mr. Gray's turn. Mr. Gray would rather shoot at Mr. White than Mr. Black, because he is better. If Mr. Gray kills Mr. White, it is just Mr. Black and Mr. Gray left, giving Mr. Black a fair chance of winning. If Mr. Gray does not kill Mr. White, it is Mr. White's turn. He would rather shoot at Mr. Gray and will definitely kill him. Even though it is now Mr. Black against Mr. White, Mr. Black has a better chance of winning than before.

#183 - Secret Code puzzle

A man wanted to get into his work building, but he had forgotten his code. However, he did remember five clues. These are what those clues were:

The fifth number plus the third number equals fourteen.

The fourth number is one more than the second number.

The first number is one less than twice the second number.

The second number plus the third number equals ten.

The sum of all five numbers is 30.

What were the five numbers and in what order?

Secret Code puzzle
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7, 4, 6, 5, 8

#184 - Find Next Number

What is the next number?

77, 49, 36, 18 ?

View Answer Discuss

The next one is 8
77 : 7*7 = 49
49 : 4*9 = 36
36 : 3*6 = 18
18 : 1*8 = 8

#185 - Extraordinary Riddle

Something Extraordinary happened on May 6th 1978 at 12:34am what was that?

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At that moment, the time, and day could be written as '12:34 5/6/78'

#186 - A Riddle

A bus driver was heading down a street in Delhi. He went right past a stop sign without stopping, he turned left where there was a 'no left turn' sign and he went the wrong way on a one-way street. Then he went on the left side of the road past a cop car. Still - he didn't break any traffic laws. Why not?

A Riddle
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He was walking

#187 - Statement Riddle

'Ferrari driver' easily beats the 'force Indian driver' in a two-car race.How did Indian newspapers truthfully report so to look as 'force Indian drive' had outdone the 'Ferrari driver'

Think ?

Statement Riddle
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The Indian newspaper reported (correctly) that the 'Ferari driver' came in next to last while the 'force india driver' came in second..

#188 - Hard Short Riddles

1)How is the moon like a dollar

2)Why is the letter I like Delhi?

3)What is the shortest complete sentence in the English language

4)If you have me, you want to share me. If you share me, you haven't got me. What am I?

5)How could a cowboy ride into town on Friday, stay two days, and ride out on Friday

View Answer Discuss

1)they both have 4 quarters.
2)They both r capital of India.
3)Go.
4)Secret.
5)His horse is named Friday!

#189 - Water Jugs Problem

Six jugs are in a row.
The first three are filled with coke, and the last three are empty.
By moving only one glass, can you arrange them so that the full and the empty glasses alternate?

View Answer Discuss

Move and then pour all coke from second glass to fifth glass.

#190 - Detective Puzzle

There are five people. One of them shot and killed one of the other five.
We know following clues:
1. Dan ran in the NY City Marathon yesterday with one of the innocent men.
2. Mike consider being a farmer before he moved to the city.
3. Jeff is a top notch computer consultant and wants to install Ben new computer next week.
4. The murderer had his leg amputated last month.
5. Ben met Jack for the first time six months ago.
6. Jack has been in seclusion since the crime.
7. Dan used to drink heavily.
8. Ben and Jeff built their last computers together.
9. The murderer is Jack brother. They grew up together in Seattle.

Consider yourself to be a famous detective "Sherlock Homles", Can you find the killer?

Detective Puzzle
View Answer Discuss

Jeff Killed Mike

1. Jack is not the murderer because he is the brother of the murderer.
2. Dan can't be the murderer since he ran a marathon, and the murderer recently had his leg amputated, and wouldn't be running a marathon of any magnitude that quickly.
3. Ben is not the murderer if he just met Jack since Jack and the murderer grew up together.
4. This leaves Jeff and Mike.

Since Jeff is still alive (he wants to install a new computer next week, present tense) he must be the murderer. Mike also didn't grow up with Jack. It has been determined that Jack, Dan, and Jeff are all alive. Ben must also be alive since Jeff plans to install Ben computer next week. This means that Jeff killed Mike.