Puzzles

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On this page you will find a collection of puzzles. A new puzzle will be added to this collection on the 1st day of each month. You will have until the last day of the month to submit your solution to each puzzle. If you find the correct solution,  10 bonus marks will be added to your mark on your next homework/evaluation.

To submit your answer to the puzzle you can either:

- send me an email with your name and your solution; (pmessier@wqsb.qc.ca) 
- hand it in to me at school in writing with your name.

NEWEST PUZZLE AT THE BOTTOM OF THIS PAGE! (PLEASE SCROLL DOWN)


PUZZLE NO.1

The St Ives Riddle

As I was going to St Ives,
I met a man with seven wives.
Every wife had seven sacks.
Every sack had seven cats,
Every cat had seven kits;
Kits, cats, sacks and wives,
How many were going to St Ives?

 

DEADLINE Tuesday, September 13, 2005

 

Puzzle No.1 Solution


PUZZLE NO.2

The Grandfather Clock

 

When a grandfather clock strikes 6 o'clock, there are 15 seconds between the first and last strokes. 

How many seconds elapse between the first and last strokes when it strikes midnight?

 

DEADLINE

 

Monday, September 26, 2005

Puzzle No.2 Solution


PUZZLE NO.3

Efficient Weighing

A bricklayer has 8 bricks. Seven of the bricks weigh the same amount and 1 is a little heavier than the others.

If the man has a balance scale how can he find the heaviest brick in only 2 weightings?

 

DEADLINE

 

Tuesday, October 11, 2005

Puzzle No. 3 Solution

 


PUZZLE NO.4

The Tarry-Town Riddle

 

Between Sing-Sing and Tarry-Town
I met my worthy friend, John Brown,
And seven daughters, riding nags,
And every one had seven bags,
In every bag were thirty cats,
And every cat had forty rats,
Besides a brood of fifty kittens,
All but the nags and bags wore mittens!
Mittens, kittens - cats, rats - bags, nags - Browns,
How many were met between the towns?

 

DEADLINE

 

Monday, October 24, 2005

Puzzle No. 4 Solution


PUZZLE NO.5

Odd numbers

 

The numbers 1 through 7 are drawn from a hat without replacement.

What is the probability that all the odd numbers will be chosen first?

 

DEADLINE

 

Friday, November 4, 2005

Puzzle No. 5 Solution


PUZZLE NO.6

The easy one

 

What letter follows OTTFFSSE?

DEADLINE

 

Tuesday, November 22, 2005

Puzzle No. 6 Solution

 


PUZZLE NO.7

What colour was the bear?

 

A man out hunting, spotted a bear due east. Taken by surprise, he ran directly north, and turned to see that the bear had not moved. Steadying himself, he took aim and shot it, by aiming due south. What colour was the bear?

 

DEADLINE

 

Monday, December 5, 2005

Puzzle No. 7 Solution

 


PUZZLE NO.8

The carpenter

 

A carpenter agrees to work on the condition that he is paid $200 for everyday that he works, while he forfeits $300 everyday that he does not work. At the end of 30 days he finds he has paid out exactly as much as he received.

How many days did he work?

 

DEADLINE

 

Friday, December 16, 2005

Puzzle No. 8 Solution

 


PUZZLE NO.9

Who can tell?

 

Twice six are eight of us,
Six are but three of us,
Nine are but four of us,
What can we possibly be?

Would you know more of us?
I'll tell you more of us.
Twelve are but six of us,
Five are but four of us, now do you see?

 

DEADLINE

 

Thursday, January 12, 2006

Puzzle No. 9 Solution

 


PUZZLE NO.10

What's the difference?

 

What is the difference between 6 dozen dozen and a half a dozen dozen?
DEADLINE

 

Tuesday, February 7, 2006

Puzzle No. 10 Solution

 


PUZZLE NO.11

Wheels around wheels

 

How many times does a coin rotate in rolling completely about another coin, of the same size, without slipping?
DEADLINE

 

Wednesday, February 22, 2006

Puzzle No. 11 Solution

 


PUZZLE NO.12

Chopsticks

 

A firewood merchant had a number of blocks to chop up for firewood. He chopped each block into eleven sticks. 

Assuming that he chopped at the average rate of forty-five strokes per minute, how many blocks would he chop up in twenty-two minutes?

 

DEADLINE

 

Tuesday, March 14, 2006

Puzzle No. 12 Solution

 


PUZZLE NO.13

The Lily in the Pond

 

A water lily doubles in size, that is, in the area of the leaf lying on the surface of the pond, every 24 hours. If it takes 30 days to cover the pond completely, after how many days did it cover exactly one half of the pond?
DEADLINE

 

Monday, March 27, 2006

Puzzle No. 13 Solution

 


PUZZLE NO.14

Three into Two

 

You have a frying pan which will take only two slices of bread at a time, and you wish to fry three slices, each on both sides. Since each slice takes 20 seconds for each side, you can certainly fry them all in 80 seconds, by doing two pieces together and then the third.

But can you fry them more efficiently?

 

DEADLINE

 

Friday, April 7, 2006

Puzzle No. 14 Solution

 


PUZZLE NO.15

A Square Chessboard

 

 

How many squares are there on an 8 by 8 chessboard?
DEADLINE

 

Monday, April 24, 2006

Puzzle No. 15 Solution

 


PUZZLE NO.16

Hectic Week

 

When the day after tomorrow is yesterday, today will be as far from Sunday as today was from Sunday when the day before yesterday was tomorrow. What day is it?

 

 

DEADLINE

 

Friday, May 5, 2006

Puzzle No. 16 Solution

 


PUZZLE NO.17

A Handy Problem

 

If you turn a left-handed glove inside-out, will it be right-handed or left- handed?
DEADLINE

 

Monday, September 25, 2006

Puzzle No.17 Solution

 


PUZZLE NO.18

An Express Problem

 

An express train takes 3 seconds to enter a tunnel which is 1 km long. If it is traveling at 120 km an hour, how long will it take to pass completely through the tunnel? 
DEADLINE

 

Tuesday, October 10, 2006

Puzzle No.18 Solution

 


PUZZLE NO.19

The Prisoner's Dilemma

 

Because he is deemed to be a foolish man who has allowed himself to be led into crime by his companions, the prisoner has been given a last chance. He is shown two doors in the courtyard, one of which leads to freedom and the other to a long sentence. Each is guarded by a warder, one of whom always lies and one of whom is impeccably honest, but he does not know which is which.

He is allowed one question, to be put to one of the warders. How can he discover which is the door to freedom?

 

DEADLINE

 

Monday, October 23, 2006

 

Puzzle No.19 Solution

 


PUZZLE NO.20

The Age of Augustus de Morgan

 

Writing in 1864, Professor de Morgan said he was x years old in the year x2 A.D. When was he born?
DEADLINE

 

Friday, November 3, 2006

 

Puzzle No.20 Solution

 


PUZZLE NO.21

The Puzzling Riddle

 

A row of four figures in value will be
Above seven thousand nine hundred and three;
But when they are halved, you'll find very fair
The sum will be nothing, in truth I declare.

 

DEADLINE

 

Thursday, November 16, 2006

Puzzle No.21 Solution

 


PUZZLE NO.22

The Fractions

 

Required of the numbers 1, 2, 3, 4, 5, 6, 7, 8, 9, 0, to compose two fractions, whose sum shall be equal to unity. Each number to be used once, and once only.
DEADLINE

 

Monday, December 4, 2006

 

Puzzle No.22 Solution

 


PUZZLE NO.23

The Boy's Age

 

"What is the age of that boy?" asked the bus driver. Flattered by this interest shown in his family affairs, the suburban resident replied:

"My son is five times as old as my daughter, and my wife is five times as old as my son, and I am twice as old as my wife, whereas grandmother, who is as old as all of us put together, is celebrating her eighty-first birthday today."

How old was the boy?

 

DEADLINE

 

Friday, December 15, 2006

 

Puzzle No.23 Solution


PUZZLE NO.24

Exploring The Desert

 

Nine travelers, each possessing a jeep, meet on the eastern edge of a desert. They wish to explore the interior, always going due west. Each jeep can travel 40 km on the contents of the engine tank, which holds a gallon of gas (about 4 liters), and each can carry nine extra gallon tins of gas and no more. Unopened tins can alone be transferred from jeep to jeep. 

What is the greatest distance to which they can enter the desert without making any depots for gas for the return journey?

 

DEADLINE

 

Thursday, January 11, 2007

Puzzle No.24 Solution


PUZZLE NO.25

The Boat In The Bath

Tommy was floating a boat in a tub of water. The boat was initially loaded with a small metal canon, but then the cannon fell into the water sank to the bottom, leaving the boat floating as before. No water got into the boat while this happened.

Did the level of the water rise, fall, or stay the same, as a result of the cannon falling overboard?

 

DEADLINE

 

Tuesday, February 6, 2007

 

Puzzle No.25 Solution


PUZZLE NO.26

The Schoolboys

 

Two schoolboys were playing on the tool shed roof. Something gave way, and they were precipitated, through the roof, on to the floor below.

When they picked themselves up, the face of one was covered with grime. The other's face was quite clean. Yet it was the boy with the clean face who at once went off and washed.

How is this explained?

 

DEADLINE

 

Wednesday, February 21, 2007

Puzzle No.26 Solution


PUZZLE NO.27

The Convivial Visitor

 

"There are only four pubs in this village", the visitor was informed, "one in each street. The village's four streets meet at the crossroads at right-angles. This street is the High Street".

"To reach the Blue Boar from the Griffin you must turn left. To reach the Dragon from the Red Lion you have to turn right".

The visitor entered three of the pubs; he arrived at the crossroads three times during this pilgrimage, turning left the first time, going straight across the second, and turning right the third time. He spent the night at the Blue Boar.

Which pub stands in the High Street?

 

DEADLINE

 

Tuesday, March 13, 2007

Puzzle No.27 Solution


PUZZLE NO.28

Lies, Lies and More Lies

 

Here are ten numbered statements. How many of them are true?

1. Exactly 1 of these statements is false
2. Exactly 2 of these statements are false
3. Exactly 3 of these statements are false
4. Exactly 4 of these statements are false
5. Exactly 5 of these statements are false
6. Exactly 6 of these statements are false
7. Exactly 7 of these statements are false
8. Exactly 8 of these statements are false
9. Exactly 9 of these statements are false
10. Exactly 10 of these statements are false

 

DEADLINE

 

Monday March 26, 2007

 

Puzzle No.28 Solution


PUZZLE NO.29

The Balloon

 

Mr. Smith's little boy sits in the back seat of a car, holding a balloon on a string. All the windows of the car are closed tight. The balloon is full of helium and is tethered by a string, which prevents it from touching the roof of the car.

The car turns left at a crossroad. Does the balloon swing left, swing right, stay upright, or do something else? And why?

 

DEADLINE

 

Tuesday April 10, 2007

Puzzle No.29 Solution


PUZZLE NO.30

The Jigsaw Puzzle

 

In assembling a jigsaw puzzle, let us call the fitting together of two pieces a "move", independently of whether the pieces consist of single pieces or of blocks of pieces already assembled.

What procedures will minimize the number of moves required to solve an "n" piece puzzle? What is the minimum number of moves needed?

 

DEADLINE

 

Monday April 23, 2007

 

Puzzle No.30 Solution


PUZZLE NO.31

The Programmer's Shirts

 

A neat computer programmer wears a clean shirt every day, If he drops off his laundry and picks up the previous week's load every Monday night, how many shirts must he own to keep him going?
DEADLINE

 

Friday, May 4, 2007

Puzzle No.31 Solution


PUZZLE NO.32

The Delightful Discounts

Buying from your favorite store you are offered a discount of 5 per cent for payment in cash, 10 per cent as a long-standing customer, and 20 per cent because it is sale time.

In what order should you take these discounts in order to pay as little as possible for your purchase?

 

DEADLINE

 

Thursday, May 17

Puzzle No.32 Solution


PUZZLE NO.33

The Simple Sums

 

Take any four-digit number, arrange the numbers in ascending and descending order to form two numbers, and subtract the smaller from the larger. Repeat the same process with the answer. What is the result - eventually?
DEADLINE

 

Tuesday, September 25

 

Puzzle No.33 Solution


PUZZLE NO.34

The Ship's Ladder

 

The good ship Algebra lay at anchor in Montreal Harbour. An interested spectator observed that a ladder was dangling form her deck; that the bottom four rungs of the ladder were submerged; that each rung was 4 cm wide and that the rungs were 22 cm apart. The tide was rising at the rate of 36 cm per hour.

At the end of two hours, how many rungs would be submerged?

 

DEADLINE

 

Tuesday, October 10

Puzzle No.34 Solution


PUZZLE NO.35

The Triangle and The Square

 

By suitably placing a 6 cm square over a triangle, I can cover up to three-quarters of the triangle. By suitably placing the triangle over the square, I can cover up to one-half of the square.

What is the area of the triangle?

 

DEADLINE

 

Wednesday, October 24

Puzzle No.35 Solution


PUZZLE NO.36

The Beer and The Wine

 

A grocer has 6 barrels of different sizes, containing 15, 16, 18, 19, 20 and 31 litres. Five barrels are filled with wine, and only one is filled with beer.

The first customer bought 2 barrels of wine, and a second customer also bought wine, but twice as much as the first.

Which is the beer barrel?

 

DEADLINE

 

Monday, November 5

 

Puzzle No.36 Solution


PUZZLE NO.37

The Ages of Man

 

A man passed one-sixth of his life in childhood, one-twelfth in youth, and one-seventh more as a bachelor. Five years after his marriage, a son was born who died four years before his father at half his father's final age.

What was the man's final age?

DEADLINE

 

Monday, November 19

Puzzle No.37 Solution


PUZZLE NO.38

The Escalator

 

A certain delivery man, who is always in a hurry, walks up an up-going escalator at the rate of one step per second. Twenty steps bring him to the top.

Next day, he goes up at two steps per second, reaching the top in 32 steps.

How many steps are there in  the escalator?

 

DEADLINE

 

Tuesday, December 4

 

Puzzle No.38 Solution


PUZZLE NO.39

The Age Problem

 

Julia and Lucy Montgomery are both 90 years old. Mary Williams, on the other hand, is half again as old as she was when she was half again as old as she was when she lacked 5 years being half as old as she is now.

How old is Mary?

DEADLINE

 

Monday, December 17

 

Puzzle No.39 Solution


PUZZLE NO.40

The Close Race

 

Two hot rodders compete in a drag race. Each accelerates at a uniform rate from a standing start. John covers the last quarter of the distance in 3 seconds; Alex covers the last third in 4 seconds.

Who won?

DEADLINE

 

Friday, January 11

Puzzle No.40 Solution


PUZZLE NO.41

The 3 Generations

 

When I am as old as my father is now, I shall be five times as old as my son is now. By then my son will be eight years older than I am now.

The combined ages of my father and myself are 100 years.

How old is my son?

 

DEADLINE

 

Wednesday, February 6

 

Puzzle No.41 Solution


PUZZLE NO.42

The Bricklayers

 

A contractor estimated that one of his two bricklayers would take 9 hours to build a certain wall and the other 10 hours. However, he knew from experience that when they worked together, 10 fewer bricks got laid per hour.

Since he was in a hurry, he put both men on the job and found it took exactly 5 hours to build the wall.

How many bricks did it contain?

 

DEADLINE

 

Wednesday, February 20

 

Puzzle No.42 Solution


PUZZLE NO.43

The Atom Smasher

 

Does the square root of an ATOM extend from A to M?

Yes, if you can assign the proper numerical values to the letters.

Here ATOM is a four-digit number and TO is a two-digit number.

 

DEADLINE

 

Tuesday, March 11

Puzzle No.43 Solution


PUZZLE NO.44

Two Men on a Horse

 

Robert and Sam have only one horse between them. Robert rides a certain time and then ties up the horse for Sam, who has been walking. Meanwhile Robert walks on ahead. They proceed in this way, alternating walking and riding.

If they walk 4 km per hour and ride 12 km per hour, what part of the time is the horse resting?

 

DEADLINE

 

Wednesday, March 26

 

Puzzle No.44 Solution


PUZZLE NO.45

A Decreasing Ratio

 

Jim was three times as old as his sister 2 years ago and five times as old 2 years before that.

In how many years will the ratio be 2 to 1?

DEADLINE Wednesday, April 9

 

Puzzle No.45 Solution


PUZZLE NO.46

A Polyhedron

 

The faces of a solid figure are all triangles. The figure has 9 vertices. At each of 6 of these vertices, 4 faces meet, and at each of the other 3 vertices, 6 faces meet.

How many faces does the figure have?

 

DEADLINE

 

Tuesday, April 22

Puzzle No.46 Solution


PUZZLE NO.47

A Special Sphere

 

The area and volume of a certain sphere are both 4-digit integers times pi.

What is the radius of the sphere?

DEADLINE

 

Monday, May 5

Puzzle No.47 Solution


PUZZLE NO.48

A Pie Shaped Field

 

A farmer owned a square field measuring exactly 2261 meters on each side. 1898 meters from one corner and 1009 meters from an adjacent corner stood a beech tree.

A neighbor offered to purchase a triangular portion of the field, stipulating that a fence should be erected in a straight line from one side of the field to an adjacent side so that the beech tree was part of the fence.

The farmer accepted the offer but made sure that the triangular portion was of minimum area. What was the area of the field the neighbor received, and how long was the fence?

 

DEADLINE

 

Tuesday, May 20

 

Puzzle No.48 Solution


PUZZLE NO.49

Changing The Base

 

An isosceles triangle has a 10 cm base and two 13 cm sides.

What other values can the base have and still yield a triangle with the same area?

DEADLINE

 

Friday, October 31

Puzzle No.49 Solution


PUZZLE NO.50

Cubes And More Cubes

 

Find a three-digit number that is the sum of the cubes of its digits.
DEADLINE

 

Friday, November 28

Puzzle No.50 Solution


PUZZLE NO.51

All The Digits

 

Arrange the digits 0 through 9 in fractional form so that:

(XXXXX)/(XXXXX) = 9

DEADLINE

 

Monday, January 5

Puzzle No.51 Solution


PUZZLE NO.52

That's Grrr8!

 

How can you add eight 8's to get the number 1,000? (You are only allowed to use additions)
DEADLINE

 

Tuesday, February 2

Puzzle No.52 Solution


PUZZLE NO.53

The Juice

 

How can you measure 1 litre of juice out of a barrel, if all you have available is a 3-litre and a 5-litre pitcher? 
DEADLINE

 

Friday, February 27

Puzzle No.53 Solution


PUZZLE NO.54

The Fractions

 

What is the number that is 5 more than the number which is one-fifth of one-fifth of one-half of 1050? 
DEADLINE

 

Tuesday, March 31

Puzzle No.54 Solution


PUZZLE NO.55

The Bag of Oranges

 

Robert bought a bag of oranges on Monday, and ate a third of them. 
On Tuesday he ate half of the remaining oranges. 
On Wednesday he looked in the bag to find he only had two oranges left.  

How many oranges were originally in the bag?

 

DEADLINE

 

Thursday, April 30

 

Puzzle No.55 Solution


PUZZLE NO.56

The Bridge

 

    A group of four people has to cross a bridge. It's dark, and they have to light the path with a flashlight. No more than two people can cross the bridge at at time, and the group has only one flashlight. It takes different time for the people in the group to cross the bridge:

Angie crosses the bridge in 1 minute,
Bill crosses the bridge in 2 minutes,
Carl crosses the bridge in 5 minutes,
Debbie crosses the bridge in 10 minutes.

How can the group cross the bridge in 17 minutes?

 

DEADLINE

 

Friday, May 29

 

Puzzle No.56 Solution


PUZZLE NO.57

The Coin Collection

 

A man decides to divide his coin collection between his children. The oldest gets 1/2 of the collection, the next gets 1/4, the next gets 1/5, and the youngest gets the remaining 49 coins. 

How many coins are in the collection?

DEADLINE

 

Wednesday, September 30

Puzzle No.57 Solution


PUZZLE NO.58

The Sisters

 

Rachel is now two-thirds of Sally's age.  In six years, Rachel will be four-fifths of Sally's age.  In 15 years, Rachel will be seven-eighths as old as sister Sally.  If they are both under the age of ten, how old are they now?
DEADLINE

 

Friday, October 30

Puzzle No.58 Solution


PUZZLE NO.59

Unique numbers

 

There is a 2-digit number that is 6 times the sum of its digits. 

What is this number?

DEADLINE

 

This was the last puzzle for this year.

SEE YOU NEXT SCHOOL YEAR!

Puzzle No.59 Solution


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