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2024 Beaver Computing Challenge
(Grade 5 & 6)

Questions

Part A

Pizza Party

Story

Jun is ordering a large pizza for four of his friends. Each of his friends has three favourite pizza toppings as shown below.

Friend Favourite toppings
Eslam Hot pepper Mushroom Cheese
Meral

Mushroom Pineapple Onion

Salma Mushroom Spinach Cheese
Wout Mushroom Cheese Onion

Jun wants to choose the three most popular toppings for the pizza he is ordering. (A topping is more popular than another topping if it is the favourite of more friends than the other topping.)

Question

Which of the following pizzas should Jun choose?

  1. A pizza with mushrooms, hot peppers, and spinach.

  2. A pizza with cheese, pineapple, and hot peppers.

  3. A pizza with cheese, mushrooms, and onions.

  4. A pizza with cheese, mushrooms, and spinach.

Nature Hike

Story

Beaver Alia hiked along a path from her home to the middle of the forest, enjoying nature along the way.

She first passed rocks . Then she passed an apple tree , followed by a bird’s nest .

Four paths, named A, B, C, and D, that each lead to the middle of the forest where Alia is. A description of the paths follows.

Question

Which of the four paths leads back to Alia’s home?

  1. Path A
  2. Path B
  3. Path C
  4. Path D

Candies

Story

Gabija offers to share the nine candies shown below with her friends.

A dish has three green dotted candies, four round striped candies, and two square blue candies.

They take some candy as follows:

Question

After this, how many candies of each type remain?

  1. two round striped candies, one square blue candy, zero green dotted candies
  2. one round striped candy, one square blue candy, zero green dotted candies
  3. two round striped candies, two square blue candies, zero green dotted candies
  4. one round striped candy, one square blue candy, one green dotted candy

Gift Box

Story

When folded, a gift box is a pyramid with a square base as shown.

A tilted view of the pyramid showing three outer faces: the square base that is coloured with red stripes, and two side-by-side triangular faces with the one to the left coloured white and the one to the right coloured blue.

The sides and bottom of the box are different colours and patterns, but only some of these are shown.

Question

Which of the following could be the outside of the gift box when it is unfolded?

  1. A square in the middle with a triangle along each of its sides. The square is orange. The top triangle is blue, the triangle on the right has red stripes, the triangle on the bottom is pink, and the triangle on the left is white.

  2. A square in the middle with a triangle along each of its sides. The square has red stripes. The top triangle is blue, the triangle on the right is orange, the triangle on the bottom is pink, and the triangle on the left is white.

  3. A square in the middle with a triangle along each of its sides. The square has red stripes. The top triangle is blue, the triangle on the right is white, the triangle on the bottom is pink, and the triangle on the left is orange.

  4. A square in the middle with a triangle along each of its sides. The square has red stripes. The top triangle is orange, the triangle on the right is white, the triangle on the bottom is pink, and the triangle on the left is blue.

Part B

Map It Out

Story

Four animals travelled across a plain. The following map shows their routes with a path from where each animal started to where they finished. However, the middle section of the map is missing.

A description of the diagram follows

Question

Which of these pieces could be the missing middle section of the map?

  1. The paths go from 1st to 3rd position, 2nd to 4th position, 3rd to 2nd position, and 4th to 1st position.

  2. The paths go from 1st to 4th position, 2nd to 3rd position, 3rd to 1st position, and 4th to 2nd position.

  3. The paths go from 1st to 2nd position, 2nd to 1st position, 3rd to 3rd position, and 4th to 4th position.

  4. The paths go from 1st to 2nd position, 2nd to 3rd position, 3rd to 1st position, and 4th to 4th position.

Boat Parking

Story

The boat slips at a marina are either reserved or available as shown. For example, boat slip 2 is reserved on Friday but available on Saturday.

A description of the diagram follows.

Tom will be parking his sailboat at the marina for two consecutive days. He will choose to arrive on either Friday or Saturday and he needs to book one boat slip that is available for both the day he arrives and the next day. He has several options available. For example, one option is for Tom to arrive on Saturday and book boat slip 1.

Question

How many options does Tom have in total?

  1. 5
  2. 6
  3. 7
  4. 8

Pushed Out

Story

Minji has a tube that is open at both ends and can hold a maximum of three balls. Balls can be added to the tube from either end. If the tube is already filled with three balls and Minji adds a fourth ball from one end, the ball closest to the other end will be pushed out, and the remaining two will shift, as shown below.

Figure 1: White ball added from the left ()

A tube starts with three balls in it. From left to right the balls are grey, white, grey. When a white ball is added on the left end of the tube, the three balls in the tube, from left to right, become white, grey, white, and a grey ball is pushed out the right end.

Figure 2: grey ball added from the right ()

A tube starts with three balls in it. From left to right the balls are grey, white, grey. When a grey ball is added on the right end of the tube, the three balls in the tube, from left to right, become white, grey, grey, and a grey ball is pushed out the left end.

Question

The tube is initially filled with the following three balls.

From left to right the balls are grey, white, grey.

What does the tube look like after Minji performs the four actions shown below in order from left to right?

grey ball added from the right,   white ball added from the right,   grey ball added from the left,   white ball added from the left

  1. From left to right the balls are white, white, grey.
  2. From left to right the balls are grey, grey, white.
  3. From left to right the balls are white, grey, white.
  4. From left to right the balls are white, grey, grey.

Sewing Machines

Story

Two types of sewing machines can each be fed two pieces of fabric to make a larger piece of fabric. They work separately as shown.

An illustration of Machine A. When Machine A is fed two rectangular pieces of fabric of the same size and shape, it places piece 1 on top of piece 2 forming a larger rectangle.

An illustration of Machine B. When Machine B is fed two rectangular pieces of fabric of the same size and shape, it rotates each piece by a quarter turn and places piece 1 to the left of piece 2 forming a larger rectangle.

Machine \(A\) sews piece 1 centered on top of piece 2.

Machine \(B\) turns piece 1 and piece 2 counter-clockwise by 90 degrees and then sews piece 1 centered to the left of piece 2.

The two machines can be combined to form even larger pieces of fabric.

Question

Pieces are fed through machines as shown by the arrows in the diagram below. What does the final large piece made by the three combined machines look like?

A description of the diagram follows.

  1. A single piece of fabric made up of the four rectangular pieces. In a row, from left to right, the pink, purple, and yellow pieces are placed vertically and side by side. The green piece, placed horizontally, is centred along the bottom edge of the row.

  2. A single piece of fabric made up of the four rectangular pieces. In a row, from left to right, the purple, yellow, and pink pieces are placed vertically and side by side. The green piece, placed horizontally, is centred along the bottom edge of the row.

  3. A single piece of fabric made up of the four rectangular pieces. In a row, from left to right, the pink piece, placed vertically, is beside the purple and yellow pieces that are placed horizontally and stacked with the purple piece on top of the yellow one. The green piece, placed horizontally, is centred along the bottom edge of the row.

  4. A single piece of fabric made up of the four rectangular pieces. In a row, from left to right, the pink, purple, and yellow pieces are placed vertically and side by side. The green piece, placed horizontally, is centred along the top edge of the row.

Part C

Online Class

Story

Nine students are sitting side by side in one row in the library while their teacher conducts an online lesson from her home. The teacher sees the class from her laptop screen as shown. Each student is using a different computer, but the teacher’s screen shows who each student is sitting next to.

The screen of a laptop shows nine windows, each centred on one of nine students. A table with the name of each student, the student that is sitting to their right, and the student that is sitting to their left can be found in the Alternative Format for Online Class.

Question

Which student is sitting in the middle (5th position) of the row in the library?

  1. Raul
  2. Lee
  3. Busara
  4. Hannah

Collecting Dolls

Story

Beaver Deana enters the maze below carrying a doll of size 1. She then goes through the maze and collects dolls of different sizes, placing smaller dolls inside larger dolls.

A maze with many paths and branches. Arrows show directions of movement through the paths. Dolls of sizes 1 through 6 are placed within the maze. The entrance, where Beaver Deana is, and the exit are at opposite corners of the maze.

Deana follows the arrows and obeys the following rule whenever she encounters a doll.

Question

What is the maximum number of dolls that Deana can collect, including the size 1 doll, by the time she reaches the exit of the maze?

  1. 3
  2. 4
  3. 5
  4. 6

Meeting Point

Story

In an area containing trees , beavers have constructed lodges . The beavers have also constructed paths that connect their lodges to trees, and some trees to one another.

A description of the diagram follows.

The beavers now want to hold a group meeting at one of the trees, but they don’t want to travel more than necessary. They want to choose a tree so that each beaver can travel to that tree using only one, two or three paths.

Question

Where should the beavers hold their group meeting?

  1. Tree \(Q\)
  2. Tree \(R\)
  3. Tree \(S\)
  4. Tree \(T\)

Balloon Machine

Story

A machine creates different designs by inflating long, skinny balloons attached to the edges of a square frame. There are five balloons labelled A, B, C, D, and E, arranged around the frame as shown.

Balloon A is on the top side of the square. D and E are on the bottom side with D to further to the left than A and E further to the right than A. B and C are on the left side with B above C.

All balloons start deflated. To create a design, the machine reads a sequence of letters, from left to right, and inflates the corresponding balloons in that order. When a particular balloon is inflated, it will continue to extend until it reaches either another balloon or the opposite edge of the frame.

For example, starting with all balloons deflated, if the machine reads the sequence E C, then it will create the following design.

Balloon E, on the bottom side of the square, is inflated so that it is long and thin. It extends vertically to meet the top side of the square, to the right of Balloon A. Balloon C, on the left side of the square, is inflated so that it is long and thin. It extends horizontally to meet Balloon E.

Question

Starting with all balloons deflated, the machine reads a sequence consisting of the five letters A, B, C, D, and E in some order and creates the design shown. How many of the balloons could have been the third balloon inflated?

Balloon B extends horizontally from the left side to the right side. Balloon A extends vertically from the top side to balloon B. Balloon E extends vertically from the bottom side to Balloon B. Balloon C extends horizontally from the left side to Balloon E. Balloon D extends vertically from the bottom side to Balloon C.

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