What are some of the best puzzles from Shakunthala Devi's book Puzzles To Is there a book in the library of puzzles by Shakuntala Devi?. Here are over tantalizing puzzles, brain teasers and riddles by one of the greatest mathematical geniuses of the twentieth century, Shakuntala Devi. Looking for books by Shakuntala Devi? See all books authored by Shakuntala Devi, including Awaken the Genius in Your Child: More Puzzles to Puzzle You.
|Language:||English, Spanish, Japanese|
|Genre:||Academic & Education|
|ePub File Size:||16.70 MB|
|PDF File Size:||17.57 MB|
|Distribution:||Free* [*Sign up for free]|
Infosys Shakuntala devi interview Puzzles with answers Shankuntaladevi puzzles,puzzles for infosys, Infosys Placement papers -Latest. infosys placement papers-New Real infosys placement papers,mumbai,bengalore,musicmarkup.info,pune If you have cleared the infosys aptitude test, you. I had this puzzles book way back in in my final year of engineering. I used it to prepare for placement quizzes. Shakuntala Devi is a well known Maths. The puzzles presented in this book are by none other than the world-renowned mathematical prodigy, Shakuntala Devi. These are meant to.
Description What is mathematics? It is only a systematic effort of solving puzzles posed by nature. Recreational mathematics, in a way, is pure mathematics and it is often difficult to distinguish pure mathematics from recreational mathematics. However, it may also be considered applied mathematics in the sense it satisfies the human need for intellectual play. And solving wits and puzzles, in a way, helps to develop wit and ingenuity. The pedagogic value of recreational mathematics is now widely recognised and creative mathematicians are never embarrassed to show their interest in recreational topics.
Use trail and error method. Angle of Hands The time is 2: Laskshmiwa was x years when x years ago. Today she is x years old. Share this: Like this: Like Loading About Praveenkumar K Founder, Editor: Global Math Project is started by famous Mathematician - James Tanton, the famous author of many math books. His exploding dots videos are must watch for math enthusiasts. My academic interests are predominantly Mathematics and Physics. History, Art are other interests. I want to learn and share with you guys!
Bookmark the permalink. Check the missed out posts Search for: Tweet to vedicmathsbypk. This work is licensed under a Creative Commons Attribution 4. On Top List. Powered by WordPress. Dropping is from north And receiving from bottom not accepted, as it is 2 directions Ans:? Some tell truth, some false and some alternators. Find out the true statements. Can u make with 5 zeros? There are three people A, B, C. Liars are of same type and Truth speaking people are of same type. Find out who is speaking truth and who is speaking false from the following statements: a A says: B is a liar.
Ans: lets assume A is speaking truth. It means B is a liar then it means A and C are not of same type. Ans: its impossible! You have to draw 3 concentric circles with a line passing thru their center without lifting hand.
Ans: Start the line complete one circle move inside circles along the line and then draw second circle. Like wise rest. A rectangular paper is there.
At a corner a rectangular size paper is taken from it. Now you have to cut the remaining paper into two equal halves. Ans: try it on the paper. You must fold the part that has complete paper and select Half of it and then fold the part that cut and selects half of it and then cut along the folding.
Value of x-a x-b..
There are 9 coins. He was standing there wondering how he is to do itl Now I offered to help and gave him some suggestions. Can you find out what was my suggestion, and how many manipulations of pouring from one vessel to the other did he require, without waste of any wine, tilting or other tricks. Can you draw four straight lines, the second beginning where the first ends, the third beginning where the second ends, and the fourth beginning where the third ends so that each dot is or at least one line?
If one-fifth of a hive of bees flew to the badamba flower, one-third flew to the slandbara, three times the difference of these two numbers flew to an arbour, and one bee continued to fly about, attracted on each side by the fragrant Ketaki and Malati, what was the number of bees?
If a player is eliminated as soon as he loses a match, how many matches are required to determine the winner? On the last day I did 51 miles, increasing my journey 4 miles each day. How many days did I travel and how far? How can these three, have each his own true Sabbath on the same day?
He wanted the picture itself to occupy 72 square inches. What should be the smallest dimensions, the canvas he is going to obtain, should possess? The four sides of the garden are known to be 20, 16, 12 and 10 rods. And it is also known that it has the greatest possible area for those sides. Can you find the area? The average price of the animals per head worked to Rs.
How many animals of each kind did he download? Before retiring they did some quick counting and found that the fruits were less than a hundred in number.
During the night one thief awoke, counted the mangoes and found that he could divide the mangoes into three equal parts if he first took one for himself. Shortly thereafter another thief awoke, counted the mangoes and he again found that if he took one Cor himself the loot could be divided into three equal parts.
He ate up one mango, bagged J of. The third thief also awoke after some time, did the same and went back to sleep. In the morning when they all woke up; and counted their mangoes, they found that the remaining mangoes again totalled 1 more than could be divided into three equal parts.
How many mangoes did the boys steal? We exchanged our phone numbers and decided to meet each other soon. When she rang up and invited me to her house this is how she gave me the number of her hduse: Numbered on my side are the bouses one, two, three and so on. All the numbers on one side of me add up exactly the same as all the numbers on the other side of me.
I know there are more than fifty houses on that side of the street, but not so manyas five hundred. Can you find Stephaine's house number?
There are an equal number of 25 paise coins, 50 paise coins and one rupee coins. How many of each are there? The cube can be cut into 27 one inch cubes by the buzz-saw. Only 6 cuts of saw are necessary to do this, while keeping the pieces together. Now, can you reduce the number of cuts by rearranging the pieces after each cut? If you can, how is it done? If you can't, why can't it be done? If they arrive at their destinations one hour and four hours respectively after passing one another, how much faster is one train running than the other?
Discussing the lease the land- lady told me: Now work it out for yourself and see how many years are there to gol How many years of unexpired lease did the property have?
Solutions The first brother is 70 inches tall, the second 72 the third 74 and the fourth brother 80 inches tall. Twenty-six minutes. Since the boys have as many brothers as sisters, there must be 1 boy more than the number of girls. If we try 2 and 1, 3 and 2, and 4 and 3, we will find that 4 boys and 3 girls is the solution to fulfil the requirement that each girl has twice as many brothers as sisters.
Naturally, the train travelling against the spin of the earth. This train will wear its wheels out more quickly, because the centrifugal force is less on this train.
However, this represents the average of the 2 speeds and not the average speed for the whole trip. One'can think of different answers for this question, but yet thecorrect answer is very simple.
All we have to consider is that the shopowner could not have possibly lost more than the tourist actually stole. The tourist got away with the bicycle which cost the shopowner Rs. And this is the exact amount of the shopkeeper's loss.
The lowest square number I can think of, contain- ing all the nine digits once and only once, is , the square of , and the highest square number under the. By experiment'we find that the only numbers that can be turned upside down and still read as a number are 0, 1, 6, 8 and 9. The numbers 0, 1 and 8 remain 0, 1 and 8 when turned over, but 6 becomes 9 and 9 becomes 6. Therefore the possible numbers on the bus were 9, 16, 81, , or However, the number isthe only number which becomes a perfect square when turned over because is the perfect square of Therefore is the correct answer.
Here is the formula that gives the minutes past twelve to which the hour hand points when the minute hand is exactly thirty minutes ahead.
The formula may be derived from the following: The Police Officer took thirty steps. In the same time'the thief took forty-eight, which added to his start of twenty-seven, carried fiim seventy-five steps. This distance would be exactly equal to thirty steps of the Police Officer. While striking 7 the clock strikes its first gong at 7 o'clock and it strikes 6 more at regular intervals. These 6 intervals take 7 seconds so that the inter- vals between gongs isiT seconds.
In order that the little girl should have disposed of the oranges she had remaining after her second 97 Therefore, if 1 orange represents half of the remaining after the second sale, then she must have sold two oranges in her second sale, leaving the 3 oranges after the first sale.
All the transactions carried out through the counterfeit note are invalid, and therefore every- body stands in relation to his debtor just where he was before I picked up the note.
A pound of cotton is heavier than a pound of gold because cotton is weighed by the avoirdupois pound, which consists of 16 ounces, whereas gold, being a precious metal is weighed by the troy pound which contains 12 ounces grams. When Tinku takes 12, Rinku and Jojo will take 9 and 14 respectively—and then they would have taken altogether thirty-five nuts.
Thirty-five is contained in twenty-two times which means all one has to do now is merely multiply 12, 9 and 14 by 22 to find that Tinku's share was , Rinku's and Jojo's Now as the total of their ages is 17i years or half Jayant was 24 and Mohini The minimum number of weights required is five and these should weight 1, 3, 9, 27 and 81 pounds.
Let's assume G is the number of glasses delivered intact. Let's assume B is the number of glasses broken. I don't know about you, but I would have handed over 5 two paise stamps, 30 one paise stamps and 7-fivepaise stamps. There isn't really any mystery, because the ex- planation is simple.
While the two ways of selling are only identical, when the number of marbles sold at three for a paise and two for a paise is in the proportion of three to two. There- fore when the first woman handed over 36 marbles and the second woman 24, they would have fetched 24 paise, immaterial of sold separately or at five for 2 paise.
But if they each held the same number of marbles there would be a loss when sold together of 1 paise in every 60 marbles. So, if they had 60 each, there would be a loss of 2 paise and if there were 90 each altogether they would lose 3 paise and so on. In the case of 60, the missing 1 paise arises from the fact that the 3 a paise woman gains 2 paise and the 2 a paise woman loses 3 paise. The couple arrived home 10 minutes earlier than ubual.
Therefore the point at which they met Thus the wife should have been at that point at five minutes to six. Since the man started to walk at five o'clock, he must have been walking for 55 minutes when hi met his wife.
My aunt's share was Rs. We can build concentric hexagons' containing 1, 6, 12, 18, 24, 30, 36 and 42 circles. When R '— becomes sufficiently large there will be room for extra circles.
And the number of saucers that can be placed on the table is: If I walk 26 steps I require 30 seconds. If I walk 34 steps I require only 18 seconds. Multiplying the 30 by 34 and 26 by 18 we get and The difference between and is When we divide this number by the difference between 30 and , i. It cannot be done.
Each rectangle covers 1 white square and one black square, because on a chess board the white and black squares are always adjacent. The two squares which we remove from the chess board are of the samecolour, and so the remaining board has two more boxes of one colour than the other.
And after the rectangles have covered 60 boxes, there will be left two squares of the same colour. Obviously the remaining rectangle cannot cover these two squares.
Just one look at the Dumber and we know that it cannot be a prime number. And if the problem has to have only one answer, this number can have only two factors. The factors are and , both of which are primes. We know that each cat killed more mice than there were cats, and therefore the correct answer, clearly, is that cats killed mice. The forcwheel is 8 feet in circumference and the hind wheel 12 feet. The entire mile was run in nine minutes. Though fr.
And the last two quarters were run in two and a quarter minutes each. The clock broken in the manner shown in the illustration below: The numerals on each of the four parts will sum to The painted area as shown in the illustration below: Though it does not leave the clear area 4' x 4', however does measure 4' from top to bottom and from side to side. We know that there were five droves with an equal number in each drove, and therefore the number must be divisible by 5.
As every one of the eight dealers bought the same number of animals, the number must also be divisible by 8. This leads us to the conclusion that the number must be a multiple of Now the highest possible multiple of 40 that will work will be found to be , and this number could be made up in one of two ways—1 cow, 23 sheep and 96 pigs or 3 cows, 8 sheep and pigs.
But the first does not fit in because the animals consisted of 'Cows, Sheep and Pigs' and Therefore the second possibility is the correct answer. Now, if the first frock usually sells for Rs.
The second frock usually sells for Rs. Again I save Rs. The difference between the first frock and the second in terms of percentage gained is a little more than 2.
Hence the- second frock is a better download. The key to the solution is that with a little bit of pencil work, it will be found, while I can walk 5 miles, my friend who started from Tumkur can walk 7 miles. Let's assume the distance between Bangalore and Tumkur is 24 miles, then the point of meeting would be 14 miles from Bangalore, and therefore I walked miles per hour while Let's assume that the man and the train normally met at the crossing at 8 A.
But when the cyclist is late, he arrives at the bend at 8. Since the train takes 5 minutes to travel the six- milerun, the speed of the train is 72 m. The woman made altogether Rs. She mads Rs. While the first was the example given, the top row must be one of the four following numbers: The manufacturer must take one flywheel made by each machine, find their total weight and compare this with the weight of the equivalent number of goodflywheelsto obtain the difference.
Then he must take 1 flywheel from machine number one, 2 flywheels from machine number The merchant must mix 70 Kilos of the Rs.
I must have had Ri. If the sari cost Rs. A little thought indicates the sari costs Rs. So the difference in cost is Rs. The date on which I met the boy was 1st January , and the boys birthday was on 31st December, The boy was 11 years old on the day I met him.
The whole brick weighs 3 lbs. They had Rs. Let's assume that the age of the ship at present is X years and of the boiler Y years. Then The ship X is twice as old as its boiler Y—X was when the ship was x—X as old as the boiler is now. The following would be the procedure in chart form: Just myself!
Only I was going to the market and I met all the others coming from the opposite direction. They will never step out with right feet together. Three socks must be taken from the drawer, because if only two were taken one might be However, the third selection must result in a pair of white or brown socks. As Rekha's share falls in through her death, the farm has now to be divided only between Rashmi and Mala, in the proportion of one-third to one- fourth—that is in the proportion of four-twelfths to three-twelfths, which is the same as four to three.
Therefore Rashmi gets four-sevenths of the hundred acres and Mala three-sevenths. The man must have lost. And the longer he went on the more he would lose—with simple cal- culations, we can draw this conclusion: In two tosses he was left with three quarters of his money.
In six tosses with twenty-seven sixty-fourths of his money, and so on. Immaterial of the order of the wins and losses, he loses money, so long as their number is in the end equal. Ten applicants had had neither mathematics nor literature training. So we can now concentrate on the remaining 90, applicants. Of the 90, twenty had had no mathematics and eight had had no literary training.
That leaves us with a remainder of 62 who have had training in both literature and mathematics. The method of working out this problem is to reverse the whole process—multiplying 2 by 10, deducting 8, squaring the result and so on.
There were sixty eyes, so there must have been thirty animals. Now the question is what com- bination of four-legged pigs and two-legged ducks adding to thirty will give 86 feet. With some pencil vork, we get the answer 13 pigs and 17 ducks. The simplest way isto find those numbers between 50 and , which are multiples of 2 and 3 leaving no remainder.
These numbers are 54, 60, 66, 72, 78, 84, 90 and By scrutiny we find that if 78 is divided by 5 it will give 15 plus 3 left over. Therefore 78 is the total number of eggs Rasool had in his basket, before the accident. And therefore he was paid Rs. If 65 minutes be counted on the face of the same watch then the problem would be impossible.
The trains travel at 25 miles per hour. Therefore they will meet after travelling for one hour and the falcon also must have been flying for one hour. Since it travels at miles per hour, the bird must have flown miles. At a raise of Rs. Mammu had 5 marbles and NawaJ 7. Th6 ages must be as follows: Thus we can work out a table showing the number of each type apartment, which should look as follows: Type of Number of Rounded out to Apartment Apartments the nearest figu 2 8.
Now we only have to arrange these numbers so that when turned upside down the result will be larger by With some experiment we will find that the number is which is , inverted.
He sold one for Rs. So he must have paid Rs. Therefore his total loss is Rs. A brick weighed 3 lbs. Therefore, 16 brickt weighed 48 lbs and 11 bricks 33 pounds. Multi- plying 48 by 33 and taking the square root we get The girl's weight must have been about 39 79 pounds. In the first three pickings you may get 1 of each colour, on the 4th pick there must be at least two of one colour. Therefore the answer is 4. The twelfth piece does not require sawing.
The train schedule must have been in the follow- ing manner: Churcbgate train into the station at 1. And Bandra train at 1. Churchgate train into the station at 1. This way each train would be arriving every ten minutes but his chances of getting the Churchgate train would be 9 times as great as of getting on the Bandra train, because if he arrives in the station between 1.
The writers spent Rs. Thus they spent altogether Rs. The five writers spent as much as four doctors, twelve doctors spent as much as nine dentists, and six dentists as much as eight bank employees. I must have entered the store with Rs. Let's assume P is a coin that's known to be perfect. The solution to this problem runs as follows: The container would be half full on the 9th day. Since the number of bacteria doubles each day, the container should be half full on the day before it became full.
Shepherd Gopal had one sheep only: A simple general solution to this problem would be as follows: Let's assume there are n number of players. Fakhruddin started with 15 quarter of a rupee pieces or Rs. Edward started with 29 quarter of a rupee pieces or Rs.
Dev started with 57 quarter of a rupee pieces or Rs.
Chunder started with quarter of a rupee pieces or Rs. Binoy started with quarter of a rupee pieces or Rs. Arun started with quarter of a rupee pieces or Rs. His salary at Rs. At Rs. Therefore neither owed the other anything. The person who must move when there are 5 matchsticks must lose the game, because if that person removes one matchstick the other person will take the remaining 4, and if that person takes two the opponent will take the remaining 3, so on and so forth.
Therefore, the person who moves v. The only correct way to make the first move is to take away 2 matchsticks and reduce the pile to 15, then no matter what your opponent does on his move, you reduce the pile to 10, then to 15 and lastly you take the remaining matchsticks. The ratio of the father and son's age is now 4 to I, and 30 years from now it will be 2 to I.
The period of thirty years equals the difference of the First I was offered 16 guavas for Rs. That would have been at the rate of 90 paise-a dozen. Thp two extra guavas gave me 18 for Rs. Let's consider the year Fortyeight has the following factors: The years 36, 48, 60 and 72 each give six occasions whereas the The bucket full of half soveriegn gold pieces are worth more since the denominations of the gold pieces make no difference.
What is most important here is the bucket containing half soveriegn gold pieces is full of gold whereas the other one is only half full. Double the product of the two distances from the wall and you get , which is the square of The sum of the two distances is 17, and when we add these two numbers 12 and 17 together and also subtract one from the other, we get the two answers that 29 or S as the radius, or half dia- meter of the table.
Let's assume X is one of the numbers and Y the other. Since the squirrel climbs 5 ft. Since they are 63 miles apart they can cover an average of 9 miles in one hour.
There- fore tho manwhohad K 15 bottlescontribat! The first man's contribution is 7 times that of the second and therefore he gets Rs. When the trains are moving in opposite direction? Hence when going in the same direction, the 'passing speed' is the speed of the passenger speed minus the speed of the The candles must have burnt for three hours and t; ree quarters as one candle had one-sixteenth of Kb total length left and the other four-sixteenths.
The first man paid Rs. The crew can row -y- of the distance per minute on still water and the stream does half that distance per minute.
The difference and sum of these two fractions are -gj- and -JF- Hence, against the stream would take minutes and with stream minutes. The correct answer is 3-rr minutes. The mixture of spirits of wine and water is in the proportion of 40 to 1, just as in the other bottle it was in the proportion of 1 to For the train to pass completely through the tunnel, it must travel 2 miles.
After 1 mile travel, the train would be completely in the tunnel, and after another mile it would be completely out. Since it takes the horse and the cow 40 days in one day of the pasture would have beea eaten. As it takes 1 day to eat of the contents of the pasture 4o w i!