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Showing posts with label Puzzles. Show all posts
Showing posts with label Puzzles. Show all posts

A box contains 12 marbles of three different colors. Green, yellow and blue- 4 each.

If you were to close your eyes and pick them at random, how many marbles must you take out to be sure that there are at least two of one color among the marbles picked out?


Answer:

In the first three pickings you may get 1 of each color. in the 4 th pick there will be at least two of one color.
So, the answer is 4.

A short man takes three steps to a tall man's two steps. They both start out on the left foot. How many steps do they have to take before they are both are stepping out on the right foot together?




Ans:

Very simple. biggrin

Thirteen teachers are in Paradox, a math conference. When they arrive at the Enigma Hotel to check in, they are told that only 12 rooms are available. Since their school had made reservations for 13 rooms, the teachers are a bit upset that they will have to find another place to stay. As they are preparing to leave and find another hotel, the manager comes out and asks if there is a problem. When she hears of their situation she assures them that the Enigma Hotel has enough space to accommodate each teacher in his or her own room. She takes two of the teachers to room #1 and promises to come back in a few minutes and take one of them to another room. She takes the third teacher to room #2, the fourth teacher to room #3, the fifth teacher to room #4 and so on, taking the twelfth teacher to room #11. She then returns to room #1 and escorts the extra teacher waiting there to room #12. All of the teachers are now happily settled in their own rooms.

Is this possible? Why or why not? question


O.K Here is the solution.

Actually, it is not possible. When the manager is putting the 12 th teacher in #11, the 13 th teacher is still waiting there and he or she must go to the #12 room. So, all the rooms are now occupied and in the first room there are two teachers and the teacher waiting there can not go to the #13 room.

Net Problem

The following is the net representation of a cube.


How will you place the letters L, A, F on the figure so that it should spell LEAF around the sides of the cube?


The Gong

If a clock takes 6 seconds to strike 6. How long the same clock take to strike 12.


Can you find the answer?

Biggest number

Can you find the biggest number you can make with three 3s?


We all know that a chess board has 64 squares. This can be completely covered by 32 cardboard rectangles, each cardboard covering just 2 squares.

Supposing we remove 2 squares of the chess board at diagonally opposite corners, can we cover the modified board with 31 rectangles? If it can be done, how can we do it? And if it cannot be done, prove it impossible.
Answer
No.It can not be done.
Each rectangle covers one white square and one black square, because on a chess board the white and black squares are always adjacent.
I think now you gor the reason.

I met a girl some days before when I was walking through a park with my children. My children and she became friends and started playing together. I decided to talk to her and during the conversation I asked her age. The smart girl replied, Two days back I was ten years old, and next year I shall be 13. If you know what is taday, you will be able to figure out my age!!!

It took some time for me to calculate her age. What about you?





Solution
The date on which I met the girl was 1st January 2007. The girl's birthday was on 31st December 1995. So The girl was 11 years old on the date I met her.

Now It is Christmas time. We are celebrating the birthday of Jesus. On this occasion we can have a birthday puzzle.

  • Take the month number of your birthday; Jan=1, Feb=2......
  • Multiply that by 5
  • Then add 6
  • Then multiply that by 4
  • Then add9
  • Then multiply that total by 5
  • Finally add the day you were born on
  • From that number , subtract 165

Then you will get the month and the day you were born.

You can ask your friends to do it tell their birth dates and become a hero.

There are two numbers with the difference of 3 between them and the difference of their squares is 51.







Can you find the numbers?

Gold Puzzle

Which is worth more, a bucket full of half a sovereign gold pieces or an identical bucket full of 1 sovereign gold pieces?






If you have the answer please post in the comments section.

You write down the following 8 digit number on a piece of paper
1 2 3 4 5 6 7 9
Then ask your friend to circle one of the digits. Say 5

You then ask your friend to multiply the 8 digit number by 45, and magically the result ends up being:

1 2 3 4 5 6 7 9
x 4 5
---------------
5 5 5 5 5 5 5 5

with the answer as a raw of the chosen number 5




The Secret!!!

When your friend circles a number, you need to multiply the chosen number by 9 in your head. Then you need to ask your friend to multiply the 8 digit number by the number you have worked out and you magically get the answer as a raw of the chosen number.

John was born in 19ab. The two digit number ab when divided by 2 gives his age on his birthday in 1999. Can you tell me how old was he?






Solution
33 years

On The Line

Today I have a very simple puzzle for you.

It is a small town railway station and there are 20 stations on that line. At each part of the 2 stations the passengers can get tickets for any of the other 19 stations.

How many different kinds of tickets do you think the booking clerk has to keep?



Solution
The answer is simple. 19x20=380

Kathy and Jane were selling sweets in the market place. Kathy at 3 for a dollar and Jane at 2 for a dollar. One day both of them were obliged to return home when each had thirty sweets unsold. They put together the two lots of sweets and and handing them over to a friend, asked her to sell them at 5 for two dollars. According to their calculation, after all, 3 for 1 dollar and 2 for 1 dollar was exactly same as 5 for 2 dollars.

Now they were expecting to get 25 dollars for the sweets as they would have got, if sold separately. But much do their surprise they got only 24 dollars for the entire lot.

Now where did the 1 dollar go? Their friend was a cheat?



Solution
There isn't really any mystery. While the two ways of selling are only identical, when the number of sweets sold at 3 for 1 dollar and 2 for 1 dollar is in proportion of 3:2. So , if Kathy had sold 36 sweets and Jane 24, they would have fetched 24 dollars (12 dollars each) , immaterial of, whatever sold separately or at 5 for 2 dollars. But if they had the same number of sweets which led to loss of 1 dollar when sold together, in every 60 sweets. So if they had 60 each (120 altogether) , there would be a loss of 2 dollars and so on.

In the case of 60, the missing 1 dollar arises from the fact that Kathy gains 2 dollars and Jane losses 3 dollars(If they share $12 each).

Kathy receives $9.5 and Jane $14.5, so that each loses $.50 in the transaction.

Today let's relax a bit.

A peasant is convicted. He gets the death penalty. The judge allows him to say a last sentence in order to determine the way the penalty will be carried out. If the peasant lies, he will be hanged, if he speaks the truth he will be beheaded. The peasant speaks a last sentence and to everybody surprise some minutes later he is set free because the judge cannot determine his penalty.

What did the peasant said?

The peasant said: "I shall be hanged!"

If the peasant was lying, he would be hanged. But that's what the peasant was saying. So he speaks the truth. But if he speaks the truth, he would be beheaded, so then he was not speaking the truth. So it is impossible for the judge to determine whether the peasant speaks the truth or not. So therefore the judge cannot determine the penalty and sets the peasant free.


Don't go away....... I need your help.......

My 2 year old son put a coin in an empty bottle and insert a cork into the neck of the bottle.
The bottle has a very nice shape. So I don't want to break it.
How could I remove the coin without taking the cork out ?




Answer

Don't worry for a solution. He himself found a way and took it out. He pulled the cork into the bottle and the coin came out.

  1. Think of a 3 digit number where all the digits are different.
  2. Reverse the digits
  3. Subtract the smaller number from the larger number
  4. Reverse the digits again
  5. Add the numbers in steps 3 and 4

Whatever 3 digit number you choose the number will always be 1089!

Here is an example

  1. 543
  2. 345
  3. 543 - 345 = 198
  4. 891
  5. 891 +198 =1089

Train Problem

Two trains start from two different stations A and B. One is going from station A to station B and another from station B to station A. If first train takes 8 hours to complete the journey and the second one takes 12 hours, when do the two trains cross each other?

Answer
The first and second train travel 1/8 and 1/12 respectively of the total distance of AB in one hour . So they cover 1/8 +1/12=5/24 of the distance AB in one hour. That means they will cross each other after 24/5 (4 hours 48 minutes) hours.

Yesterday I couldn't write. Today I hoped to write about basic geometric concepts. But today also I am very busy and I haven't enough time to write a long topic.

So we can have a small puzzle today. This is an ancient problem dating back to about 310 A.D.
Demochares had one-fourth of his life as a boy, one-fifth as a youth , one-third as a man, and has spent 13 years in his dotage. How old was Demochares?


Another problem of this kind:
A stone weights one Kilogram and half of its weight. What is the actual weight of the stone?

Solutions:
First Question
Let x be Demochares's age.
Then, x/4+x/5+x/3+13=x
ie 47x/ 60+13=60
==>47x/60=47
==>x=60
So, Demochares was 60 years.


Second Question
2 kilogram

What is the peculiarity of 1729?

This number is known in the name of the famous mathematician Ramanujan.




Answer

This is the one and only one number which can be written as the sum of the cubes of two numbers in two different ways.

10^3 + 9^3 =1729
12^3 + 1^3 = 1729