Brainteaser Puzzles | Mind Teaser | Math Logic

Oct 11, 2007

The Expedition (Logic Brainteaser Puzzle)

An expedition to explore the Lurgi desert is about to set off. It consists of four men and each one has enough food to last him five days. After some distance, one man gets sick and has to turn back. He takes with him just enough food to last him till he gets back to base. Then the second man does the same, and the third. How many day’s journey was the last man able to make into the desert and get back safely? (You must assume that the men only travel in units of one day and that they can give food to the others.)

Again, in order to make it more interesting, I am not giving the answer or the clue straight. Please try to give your answer in the comment box at my blog or by yahoo groups email, I’ll check it out as soon as possible, and I’ll give the clue and the answer eventually. Thx guys!!

Chess Player (Logic Brainteaser Puzzle)

Two men played five games of chess. They each won the same number of games. How was this possible?

Again, in order to make it more interesting, I am not giving the answer or the clue straight. Please try to give your answer in the comment box at my blog or by yahoo groups email, I’ll check it out as soon as possible, and I’ll give the clue and the answer eventually. Thx guys!!

Oct 9, 2007

The murder (Logic Brainteaser Puzzle)

This is the hardest question so far, please try to solve it!!

One evening there was a murder in the home of married couple, their son and daughter. One of these four people murdered one of the others. One of the members of the family witnessed the crime.

The other one helped the murderer.

These are the things we know for sure:

1. The witness and the one who helped the murderer were not of the same sex.

2. The oldest person and the witness were not of the same sex.

3. The youngest person and the victim were not of the same sex.

4. The one who helped the murderer was older than the victim.

5. The father was the oldest member of the family.

6. The murderer was not the youngest member of the family.

Who was the murderer?

Clue:

Establish what we know about the youngest person first. This person cannot have been either the victim three, the helper four or the killer five. Then work out who was oldest, youngest, etc. After this draw up the various possibilities about who could have been what.

We know from (3) that the youngest person was not the victim, from (4) that the youngest person was not the helper and from (6) that the youngest person was not the killer. The youngest person can only have been the witness therefore. If we make up a chart there are now three possible combinations:

Oldest person (father) H H M

Next to oldest (mother) V M H

Next to youngest (son) M V V

Youngest (daughter) W W W

(H = Helper ; V = Victim ; M = Murderer ; W = Witness)

We can work out from (5) that the father was the oldest, from (2) that the youngest person must have been the daughter. Therefore the next to the youngest must have been the son and the next to the oldest, the mother.

Of three possibilities: the first is impossible (from (3) – the youngest person and the victim were of different sexes); the third is also impossible (from (1) – the witness and the helper were of different sexes). Therefore only the second possibility holds – and the mother was the murderess.

The Kidnappers (Logic Brainteaser Puzzle)

When the Rajah’s daughter was kidnapped, he arrested three young men. The suspects were brought before his wise old guru.

Ravi said: ‘Gopal did it.’

Gopal said: ‘But that’s not true.’

Kushwant said: ‘It was Ravi who did it.’

Ravi said: ‘What Kushwant says next will be true.’

Gopal said: ‘What Ravi has just said is false.’

Kushwant said: ‘Ravi has made two false statements.’

The guru meditated for a few minutes before whispering the name of the guilty person in the Rajah’s ear. Which name?

Again, in order to make it more interesting, I am not giving the answer or the clue straight. Please try to give your answer in the comment box at my blog or by email, I’ll check it out as soon as possible, and I’ll give the clue and the answer eventually. Thx guys!!

Oct 7, 2007

Surprising Memory (Just Playing Around)

An easy way to surprise your friends will be for you to memorize the following calculations:

1x9+2=11

12x9+3=111

123x9+4=1111

1234x9+5=11111

12345x9+6=111111

123456x9+7=1111111

1234567x9+8=11111111

12345678x9+9=111111111

Or:

9x9+7=88

98x9+6=888

987x9+5=8888

9876x9+4=88888

98765x9+3=888888

987654x9+2=8888888

9876543x9+1=88888888

98765432x9+0=888888888

Guessing The Number (Just Playing Around)

Here’s a trick that will make your friends think you can guess any number they think of.

-Choose a number between 0 and 50 and write it down on a piece of paper. Fold the paper and give it to a friend who mustn’t look at it.

-Ask your friend to choose a number between 50 and 100. He mustn’t let you know what it is.

-Subtract the number you had chosen (and written on the piece of paper) from 99.

-He must then take off the first digit on the left and add it to the number.

-Then, ask him to subtract this number from the one he had originally chosen.

The resulting number will be the one you had written on the paper at the very beginning!

Small Village (Logic Brainteaser Puzzle)

I live in a very small village where many people are related to each other. For example Tom, Dick and Harry are garage owner, vicar and solicitor but not in that order. Tom is the vicar’s father-in-law and Dick is the solicitor’s son-in-law. Everyone was at the church last Saturday when Harry married the garage owner’s daughter. Who does which job? (By the way, the people are very moral in our village, so none of the three has been married more than once.)

Again, in order to make it more interesting, I am not giving the answer or the clue straight, and this one is pretty tough. Please try to give your answer in the comment box at my blog or by email, I’ll check it out as soon as possible, and I’ll give the clue and the answer eventually. Thx guys!!

The Pawnbroker (Logic Brainteaser Puzzle)

As I reached the ticket office I realized I had no cash, only a \$10 postal order. The fare to Cambridge was \$7 and the booking clerk would not accept my postal order. Luckily there was a pawnbroker nearby, so I went in and pawned my postal order for \$7. On my way back into the station, I met Patrick, a friend of mine, who offered to buy the pawn ticket from me for \$7, to save me the trouble of coming back to London. Naturally I agreed, then rushed in and bought my ticket. When I got to Cambridge I still had \$7 of course.

So who lost?

Clue: If the man who travelled to Cambridge had been able to use his \$10, he would have had \$3 left after deducting the fare. Instead he has \$7. So \$4 has come from somewhere. In order to redeem the postal order, someone will have to pay the pawnbroker back his \$7..

The Wrong Finger (Just Playing Around)

Give a friend the following instructions:

-hold your arms in front of you

-cross them

-turn them so that your palms face each other

Then point to one of his fingers (don’t touch it!) and ask him to move it. You will probably find that he will move the wrong finger. Ha-ha. Give it a try..

Oct 5, 2007

The Records (Logic Brainteaser Puzzle)

Jack said, ‘if I had one of your records, I’d have as many you.’ Bob said, ‘If I had one of yours, I’d have twice as many as you!’ How many records had each?

Clue for the Puzzle: Try out one or two possible answers. For example, suppose Jack had three records, and Bob five. Then if Bob gives him one, each will have four. But if Jack gives one to Bob, he has six and Jack has only two. So that will not work. Try another pair of numbers in the same way.

Answer for the Puzzle: Jack has five records and Bob has seven.

The Prescription (logic Brainteaser Puzzle)

Yesterday my doctor prescribed some tablets. There were five in the box. He told me to take one every half hour. How long did they last me?

Clue for the answer: What did I do as soon I get home?

Answer for the Puzzle: They lasted 2 hours.

The Bus and The Cyclist (Logic Brainteaser Puzzle)

The bus from Edinburgh to London left at 8 a.m. An hour later a cyclist started out from London for Edinburgh. When the bus and the cyclist meet, which of the two will be further from Edinburgh?

Clue for the Puzzle: You don’t need math to solve this!!

Answer for the Puzzle: They are exactly the same distance from Edinburgh of course. Ha-ha..

Nine (Math Brainteaser Puzzle)

How many times does the digit 9 appear between 1 and 100? Give the answer in 10 seconds!!

Answer for the Puzzle: 20 times

Fish Fingers (Logic Brainteaser Puzzle)

I wanted to fry some fish fingers for myself and my two guests. I had three fish fingers but the frying pan only holds two at a time. it takes 30 seconds to fry one side of a fish finger. So how did I manage to fry both side of all three fish fingers in one and half minutes?

Clue for the Puzzle: Obviously I could not do it by frying two on one side and then on the other. Suppose I had fried two on one side and then taken out and replaced it with the third?

Answer for the Puzzle: I put in two and fried them on one side (30 seconds). I tool one out, turned one over and put the third in (30 seconds). Now I had one cooked on both sides and two cooked on one side. So I turned over the one in the pan and put back the one I had taken out earlier (30 seconds) and all three were cooked.