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The Answers

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Page 1: The Answers. Roses are Red… The Queen of Hearts hates white roses. Three of her gardeners were painting them red. They are living playing cards, specifically

The Answers

Page 2: The Answers. Roses are Red… The Queen of Hearts hates white roses. Three of her gardeners were painting them red. They are living playing cards, specifically

Roses are Red…The Queen of Hearts hates white roses. Three of her gardeners were painting them red. They are living playing cards, specifically the Two of Clubs, Five of Clubs and Seven of Clubs.The Two & the Five working together can paint 16 roses per hour.The Five & the Seven can paint 18 roses between them in an hour.The Two and the Seven can combine their labours to paint 10 roses per hour.132 roses need to be painted, so how long would it take to accomplish this if all three playing cards cooperated?

Page 3: The Answers. Roses are Red… The Queen of Hearts hates white roses. Three of her gardeners were painting them red. They are living playing cards, specifically

Roses are Red…

T + F = 16

F + S = 18

T + S = 10

Add all 3 together gives us:

2T + 2S + 2F = 44 T + S + F = 22

So 132 Roses would take 6 hours

Page 4: The Answers. Roses are Red… The Queen of Hearts hates white roses. Three of her gardeners were painting them red. They are living playing cards, specifically

Roses are Red…

T + F = 16

F + S = 18

T + S = 20

By combining all the equations,

T = 4, F = 12, S = 6 T + S + F = 22

So 132 Roses would take 6 hours

Page 5: The Answers. Roses are Red… The Queen of Hearts hates white roses. Three of her gardeners were painting them red. They are living playing cards, specifically

A Pawn like AliceIn Through the Looking-Glass, Alice plays as a pawn on a giant square chessboard, which has 64 squares in total, arranged in equal numbers of ranks (rows) and files (columns). She has to reach the highest rank – the 8th rank – to be crowned a queen.Imagine a second square chessboard (let’s call this X) with an unknown number of squares. A third square chessboard (Y) has 99 more squares than X, while a fourth square chessboard (Z) has 200 squares more than X. For Alice to become a queen on chessboard X, which rank must she reach?

Page 6: The Answers. Roses are Red… The Queen of Hearts hates white roses. Three of her gardeners were painting them red. They are living playing cards, specifically

A Pawn like Alice

x² + 99 = y²

x² + 200 = z²

So, z² – y² = 101

( z – y ) ( z + y ) = 101

101 is prime, so ( z – y ) = 1, ( z + y) = 101

So y = 50, z = 51

So x² = 50² – 99 = 2401 = 49²

Page 7: The Answers. Roses are Red… The Queen of Hearts hates white roses. Three of her gardeners were painting them red. They are living playing cards, specifically

The Mad Hatter’s Riddle

At the Mad Hatter’s Tea Party, the other diners give poor Alice a series of increasingly contrived riddles. The Hatter tells her that 14! = 871a82b12cdand challenges her to find the four unidentified digits, in order to calculate the value of 14!. Can you help her? [Hint: 14! = 14 × 13 × 12 × 11 × 10 × 9 × 8 × 7 × 6 × 5 × 4 × 3 × 2 × 1] Do not use a calculator or computer. You must carefully explain all of yourlogical reasoning.

Page 8: The Answers. Roses are Red… The Queen of Hearts hates white roses. Three of her gardeners were painting them red. They are living playing cards, specifically

The Mad Hatter’s Riddle

871a82b12cd

First, the easy bit!

10, 5 and 2 are all factors, so c & d are both 0.

Page 9: The Answers. Roses are Red… The Queen of Hearts hates white roses. Three of her gardeners were painting them red. They are living playing cards, specifically

The Mad Hatter’s Riddle

871a82b1200

9 must be a factor, so the digits must add up to 9.

8 + 7 + 1 + 8 + 2 + 1 + 2 + a + b = 29 + a +b

So a and b must add up to 7 or 16.

11 is also a factor, so alternating digits add up to two numbers with a difference of 11

8 + 1 + 8 + b + 2 = 19 + b, 7 + a + 2 + 1 = 10 + a

So 9 – a + b = 11 b – a = 2

Page 10: The Answers. Roses are Red… The Queen of Hearts hates white roses. Three of her gardeners were painting them red. They are living playing cards, specifically

The Mad Hatter’s Riddle

871a82b1200

b – a = 2 and a + b = 7 impossible

b – a = 2 and a + b = 16 a = 7, b = 9

So 14! = 87,178,291,200

Page 11: The Answers. Roses are Red… The Queen of Hearts hates white roses. Three of her gardeners were painting them red. They are living playing cards, specifically

Chair DespairThe Mad Hatter’s Tea Party, hosted by the Hatter, has three guests: Alice, the Dormouse and the March Hare.

He sets named places for all four diners, but is very angry to discover that everyone has sat down so that no one is sitting in the correct chair!

How many possible ways are there for this to happen? Explain why.

Page 12: The Answers. Roses are Red… The Queen of Hearts hates white roses. Three of her gardeners were painting them red. They are living playing cards, specifically

Chair Despair

Mad Hatter

March Hare

Dormouse

Alice

Alic

e

Dormouse

Mad Hatter

March H

are

There are 4 chairs, so there are 4! arrangements.

Now we eliminate those where at

least one person in the right seat.

Page 13: The Answers. Roses are Red… The Queen of Hearts hates white roses. Three of her gardeners were painting them red. They are living playing cards, specifically

Chair Despair

A A A A A A A D D D D D D M M M M M M H H H H H H

D D D M M H H A A M M H H A A D D H H A A D D M M

H H M D H M D H M H A M A D H A H D A D M A M A D

M M H H D D M M H A H A M H D H A A D M D M A D A

Page 14: The Answers. Roses are Red… The Queen of Hearts hates white roses. Three of her gardeners were painting them red. They are living playing cards, specifically

The Cat’s Whiskers

The Cheshire Cat has made himself invisible to hide away from Alice and is sat on the perimeter wall of the Duchess’s garden. The garden is rectangular in shape, with the perimeter walls running from North to South and from West to East. He is located 5 metres from the North-East corner of the garden, 14 metres from the South-West corner, and 10 metres from one of the other two corners. The Northern wall is longer than the Western wall.Use a scale of 1cm = 1m to draw diagrams, accurate to the nearest mm, showing the possible measurements of the Duchess’s garden and marking the Cheshire Cat’s location on each diagram. How far is he from the fourth corner?

Page 15: The Answers. Roses are Red… The Queen of Hearts hates white roses. Three of her gardeners were painting them red. They are living playing cards, specifically

The Cat’s WhiskersFirst, the garden is this way around.

Now if AC = 10m and CD = 14m, AD must be √96 ≈ 9.8m

A B

ED

C

Page 16: The Answers. Roses are Red… The Queen of Hearts hates white roses. Three of her gardeners were painting them red. They are living playing cards, specifically

The Cat’s WhiskersFirst, the garden is this way around.

This now gives us BE ≈ 9.8m, BC = 5m, so CE = √121 = 11m

A B

ED

C

Page 17: The Answers. Roses are Red… The Queen of Hearts hates white roses. Three of her gardeners were painting them red. They are living playing cards, specifically

The Cat’s Whiskers

Similarly, if CE = 11m and CB = 5m, BE = √75 ≈ 8.7m.

AB

ED

C

Page 18: The Answers. Roses are Red… The Queen of Hearts hates white roses. Three of her gardeners were painting them red. They are living playing cards, specifically

The Cat’s Whiskers

Now that we know AD ≈ 8.7m and CD = 14, then AC = √121 = 11m.

AB

ED

C

Page 19: The Answers. Roses are Red… The Queen of Hearts hates white roses. Three of her gardeners were painting them red. They are living playing cards, specifically

Jail Break!To avoid their fate, 20 prisoners escape from the Queen of Hearts’ jail into the population in her garden. In an effort to recapture them, the Queen has her soldiers seal off the garden immediately and then arrest 140 characters from the garden at random. It is discovered that only 7 of those arrested were among her original prisoners! Estimate the total population of characters in the garden after the escape but before the new arrests. (Assume that the original prisoners did not get beyond the garden.)

Page 20: The Answers. Roses are Red… The Queen of Hearts hates white roses. Three of her gardeners were painting them red. They are living playing cards, specifically

Jail Break!

Page 21: The Answers. Roses are Red… The Queen of Hearts hates white roses. Three of her gardeners were painting them red. They are living playing cards, specifically

Two Pairs of Squares

Lewis Carroll was actually the pen name of Charles Dodgson, whose day job was as a mathematician at the University of Oxford.

One entry in his diary mentioned his discovery that, when he doubled the sum of any two square numbers, the answer he obtained could always be written as the sum of two square numbers.

Show that this is true for 22 and 32.

Now try it for 52 and 72, then for 102 and 132.

What do you notice about the relationship between the two original square numbers in each case and the pair of square numbers that is equal to twice their sum?

Prove why this always works.

Page 22: The Answers. Roses are Red… The Queen of Hearts hates white roses. Three of her gardeners were painting them red. They are living playing cards, specifically

Two Pairs of Squares

2 (𝑥2+𝑦2 )=(𝑥+𝑦)2+(𝑥− 𝑦 )2

Page 23: The Answers. Roses are Red… The Queen of Hearts hates white roses. Three of her gardeners were painting them red. They are living playing cards, specifically

Two Pairs of Squares