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2019 Beaver Computing Challenge
(Grade 5 & 6)

Questions

Part A

Cloud Communication

Story

Smoke signals were used by different groups of ancient peoples to send messages. A very simple code using small and large smoke clouds is given below.

north east south west
Smoke Clouds Five clouds from top to bottom are as follows: small, large, small, large, small. Five clouds from top to bottom are as follows: large, large, large, large, large. Five clouds from top to bottom are as follows: large, small, large, small, small. Five clouds from top to bottom are as follows: small, small, small, small, large.

Messages are read from top to bottom. The following message contains an error. Either one small cloud should be a large cloud or one large cloud should be a small cloud.

Five clouds from top to bottom are as follows: small, large, large, large, small.

Question

What is the correct message?

  1. north
  2. east
  3. south
  4. west

Beaver Coins

Story

Beavers use coins with the following values:

Coin Coin with 16 kernels. Coin with 8 kernels. Coin with 4 kernels. Coin with 2 kernels. Coin with 1 kernel.
Value 16 8 4 2 1

Question

Which of the following total values can be made using exactly three coins?

  1. 23
  2. 2
  3. 38
  4. 13

Push-Away Parking

Story

In the parking lot shown, each car is either parked in a parking space or in front of two parking spaces.

13 cars, labelled A through M, are parked side by side in 13 parking spaces in a row. Car N is parked in front of the spaces with Cars B and C, with the length of Car N equal to the width of these two spaces. Similarly, Car O is parked in front of Cars F and G, Car P is in front of Cars H and I, Car Q is in front of K and L.

Cars that are parked in front of two parking spaces may be moved forward or backward in order to allow blocked cars to exit. For example, Car A is not blocked and can exit without any other cars moving; however, Car L is blocked by Car Q. If Car Q is moved, then Car L can exit.

Question

Which car cannot exit its parking space unless two different cars move?

  1. Car G
  2. Car H
  3. Car I
  4. Car B

Box of Balls

Story

A beaver has a box with an opening on the right-hand side.

Three balls lie in a row on the left side of a narrow and long box. From left to right, the balls are marked with a star, a heart, and a circle.

At any time, the beaver can take out the rightmost ball from the box, or put in a new ball from the right. For example, if the beaver wants a ball with a triangle in between a ball with a heart and a ball with a circle, it needs to take out a ball with a circle., put in a ball with a triangle., and then put in a ball with an orange circle..

Now suppose the beaver has five balls in the box as shown, and two balls, one with a triangle and one with a square, out of the box.

Five balls lie in a row on the left side of the box. From left to right, the balls are marked with a heart, circle, star, trapezoid, and a pentagon.

The beaver wants the balls in the box to be in the order: heart, circle, star, triangle, trapezoid, square, pentagon.

Question

What should the beaver do?

  1. Take out pentagon, take out trapezoid, put in triangle, put in square, put in trapezoid, and then put in pentagon.
  2. Take out pentagon, take out trapezoid, put in triangle, put in trapezoid, put in square, and then put in pentagon.
  3. Take out pentagon, put in triangle, put in square, and then put in pentagon.
  4. Take out pentagon, take out trapezoid, put in pentagon, put in square, put in square, and then put in triangle.

Part B

Koko’s Animals

Story

Koko has six animals and needs to place each one in its own pen. Two animals cannot be placed in touching pens if one animal will eat the other. In the diagram shown, arrows point from an animal to all the other animals that it will eat.

Pens
A box is divided into three columns. The first column has one pen; the second column has two equal-sized pens divided top and bottom; the third column has three equal-sized pens divided top, middle, and bottom. In the second column, the top pen touches the pen in the first column and the top two pens in the third column while the bottom pen touches the pen in the first column and the bottom two pens in the third column.

Who Eats Who
Arrows point from the salamander and the chicken to the worm. Arrows point point from the fox and the wolf to the chicken. An arrow poins from the wolf to the sheep.

For example, the wolf will eat the chicken, but the wolf will not eat the worm.

Question

Which of the following choices is not a good placement?

(A)In the first column, the only pen has the chicken. In the second column, the top pen has the sheep and the bottom pen has the salamander. In the third column, the top pen has the worm, the middle pen has the fox, and the bottom pen has the wolf.
(B)The first column has the worm. The second column has the sheepm then the fox. The third column has the chicken, the salamander, then the wolf.
(C)The first column has the wolf. The second column has the fox, then the salamander. The third column has the worm, the sheep, then the chicken.
(D)The first column has the chicken. The second column has the sheep, then the salamander. The third column has the fox, the worm, then the wolf.

Special Towers

Story

Consider the towers shown.

Eleven towers in a row with the 1st on the left and the 11th on the right. The 2nd tower in the row is the shortest tower and the 10th tower is the tallest. The towers from shortest to tallest are as follows: 2nd, 1st, 3rd, 5th, 4th, 7th, 6th, 8th, 9th, 11th, 10th.

A tower is special if all towers to the left of it are shorter, and all towers to the right of it are taller.

Question

How many special towers are there?

  1. 1
  2. 2
  3. 3
  4. 4

Ancient Code

Story

Beaver Cleveria discovered a table of symbols carved in wood.

An alternative format for the diagram follows.

After studying the table, Cleveria figures out that it is an ancient code. The symbol assigned to a row and the symbol assigned to a column are combined to form a single image. This image is the code for the letter where that row and column meet. For example, the letter H is encoded as shown:

H is in the the column corresponding to the circle with 3 lines and in the row corresponding to the spiky circle. This results in a code that has a circle with 3 lines placed inside a spiky circle.

Later, Cleveria sees the following coded message on a tree:

A description of the diagram follows.

Question

What is the message?

  1. LOVEWATER
  2. SLEEPDAYS
  3. LOVEMYSUN
  4. CAREFORME

Beaverumba

Story

There are five positions in the beaverumba dance. Each position after the first involves moving either exactly one arm or exactly one leg from the position before it. Robert remembers the first position of the dance but forgets the correct order of the other four positions.

First position
Both arms down and both legs down.
Other four positions
A position with both arms up and both legs up; a position with left arm up and left leg up; a position with left arm up; a position with both arms up and left leg up.

Question

What is the third position of the dance?


  1. Both arms up and both legs up.

  2. Left arm up, and other three limbs down.

  3. Left arm up, right arm down, left leg up, and right leg down.

  4. Both arms up, left leg up, and right leg down.

Part C

Space Travel

Story

An astronaut’s map is shown. It shows all of the possible travel routes between planets. For each route, it shows whether it can be travelled by rocket Rocket or by spaceship Spaceship, or by both rocket and spaceship.

A description of the map follows.

For example, A rocket and two spaceships. is a list of space vehicles that will take the astronaut from Venus to Saturn.

Suppose the astronaut wants to travel from Neptune to Earth.

Question

Which of the following is not a list of space vehicles that the astronaut could take?

  1. Spaceship, Spaceship, Rocket
  2. Rocket, Spaceship, Spacheship, Spaceship, Rocket
  3. Rocket, Rocket, Spaceship
  4. Rocket, Spaceship, Rocket, Spaceship

Plates

Story

A beaver believes plates are only arranged properly if all the large plates are on the left, followed by all the medium plates, followed by all the small plates. For example, the beaver believes the three large plates, three medium plates, and two small plates shown are arranged properly.

A row of ten slots for plates. In the slots, from left to right, are three large plates, three medium places, two small places, then two empty slots.

The beaver would like to add a large plate and arrange them properly.

Question

Of the eight original plates, what is the fewest number of plates that must be moved?

  1. 2
  2. 3
  3. 4
  4. 5

Seating Plan

Story

Berto and seven of his friends are sitting in a circle. They are all facing inwards.

Eight chairs are arranged equally spaced around a circle. Alice's chair is directly across from Duc's chair.

We know the following facts about where the friends are sitting:

  1. Alice is sitting directly across from Duc, as shown.
  2. Greta and Eugene are both sitting beside Haakim.
  3. Franny is not sitting beside Alice or Duc.
  4. There is someone who is sitting next to both Greta and Chika.
  5. Eugene is beside Duc, on Duc’s left.

Question

Which of these orders of friends, in a clockwise manner, is correct?

  1. Alice, Berto, Greta, Duc, Chika, Eugene, Franny, Haakim
  2. Alice, Greta, Haakim, Eugene, Duc, Berto, Franny, Chika
  3. Alice, Chika, Franny, Berto, Duc, Eugene, Haakim, Greta
  4. Alice, Haakim, Eugene, Greta, Duc, Franny, Berto, Chika

Picking Flowers

Story

A beaver visits 9 of the 15 sections in the garden shown. It begins at the top left section and ends at the bottom right section. The beaver only moves down or right and it picks all the flowers in each section it visits.

A description of the garden follows.

Question

What is the maximum number of flowers that the beaver can pick?

  1. 39
  2. 38
  3. 58
  4. 41