The Bebras Challenge is an international challenge on informatics and computer fluency for all age of school students.

*It is performed at schools using computers.* The contestants are usually supervised by teachers who may integrate the challenge in their teaching activities.

The challenge has two types of tasks: a *multiple choice questions* and *interactive problems*.

Number of tasks varies year-by-year from 18 to 24 questions of different difficulty to be solved in 40, 45 or 55 minutes.

For each multiple choice question a choice of four answers is provided. There are interactive tasks as well.

**Point Counting:**

For every correct answer there is 6 (easy), 9 (medium) or 12 points (hard).

If no answer is given the score doesn’t change;

Minus one third of the possible points if the answer is incorrect.

**There are 6 different levels of this competition, but the awards are by 12 individual levels:**

- Pre-Ecolier (Primary 1 & 2 / Grade 1 & 2)
- Ecolier (Primary 3 & 4 / Grade 3 & 4)
- Benjamin (Primary 5 & 6 / Grade 5 & 6)
- Cadet (Secondary 1 & 2 / Grade 7 & 8)
- Junior (Secondary 3 & 4 / Grade 9 & 10)
- Senior (Junior College / Poly 1 & 2/ Grade 11 & 12)

Registration can be done through the school by signing up online on: Teachers Website

**Detailed Procedure can be found HERE**

Once registered, teachers can register students and make changes on the teachers website.

Teachers will then be able to generate username and password for each of their students.

**On the Day of the Contest**

Teachers will supervise students to take the Bebras Challenge online on the Student Website.

Students have to know their username and password to take the challenge.

All participants can use pencil, paper and a calculator.

**After the Competition**

Bebras Challenge results will be made known 2 weeks after the competition and emailed to the teachers.

Teachers will also be able to download the results on the teachers website.

The following are sample Bebras tasks for all levels.

More sample tasks can be found on the Student Website and Bebras.Org

*Only nine keys *

*(Age group: Pre-Ecolier, 7-8; Difficulty: easy) *

Daniel is sending text messages from his old phone.

For every letter he has to press the proper key once, twice, three or four times, followed by a short pause.

In order to type ‘C’ he has to press the number 2 key three times because ‘C’ is the third letter written on this key.

In order to type ‘HIM’ he has to press the number 4 key twice, followed by the number 4 key 3 times and finally the number 6 key once.

Daniel presses exactly six times to enter the name of a friend.

What is the name of his friend?

a. Miriam b. Iris c. Emma d. Ina

*Abacus *

*(Age group: Ecolier, 9-10; Difficulty: medium) *

A number is represented on a Chinese abacus by the position of its beads.

The value of a bead on the top part is 5; the value of a bead on the bottom part is 1. The abacus is reset to zero by pushing the beads away from the centre.

To represent the number 1 746 503 the appropriate beads are moved towards the centre of the abacus.

What number does the following abacus represent?

*Village Network *

*(Age group: Benjamins, 11-12; Difficulty: medium) *

A village is receiving a new wireless network consisting of several Network towers. The network will offer WiFi to all the villagers.

Every network tower has the coverage area shown below.

The red star represents the network tower. Only in the twelve shaded squares surrounding the tower will a house get a WiFi signal.

The picture below shows a map of the village divided into squares.

Every triangle ▲ represents a house. A network tower cannot be built inside a square, only on the cross point of the village squares. The coverage areas may overlap.

What is the minimum number of network towers required to provide coverage to every house?

** **

*Clinging Robot*

*(Age group: Cadets, 13-14; Difficulty: medium) *

The clinging robot walks along the road, always clinging to one side of the road. The clinging robot knows four commands:

**Command Explanation**

START Start walking along the side where you are standing

CONTINUE Keep walking along the side where you are walking

SWITCH Switch to the other side of the road and keep walking

STOP Stop walking

A command is executed when setting off and whenever the robot walks across one of the grey magnetic devices on the road. All these devices are indicated on the map.

The clinging robot is given the following instruction set:

START SWITCH CONTINUE CONTINUE CONTINUE STOP

The robot starts as indicated in the picture. Click on the grey spiky circle where the robot stops.

*Friends *

*(Age group: Juniors, 15-16; Difficulty: medium) *

Lucia and her friends are registered in a social network. Here are Lucia’s friends and their friends.

*A line means friendship between two people. For example Monica is Lucia’s friend but Alex is not Lucia’s friend. *

- If someone shares a photo with some of his/her friends then those friends can also comment on it.
- If someone comments a photo then all his/her friends can see the comment and the photo, but cannot comment on it unless they originally could.

Lucia has uploaded a photo. With whom can she share it if she *does not want* Jacob to see it?

*Broken machines *

*(Age group: Seniors, 17-18; Difficulty: medium) *

Hans constructed three machines, which were all supposed to output the second largest value from a list of four numbers.

In other words, if numbers represented by a, b, c and d are input to a machine in this order, the results would be as follows:

Machine 1: outputs max(min(a,b), max(c,d))

Machine 2: outputs max(max(a,b), min(c,d))

Machine 3: outputs max(min(a,b), min(c,d))

For example, if Hilda inputs the numbers 4, 3, 2, 1 into Machine 1, the output she will get is 3, which is indeed the second largest value.

However, as she continued working with the devices she quite quickly realised that none of the machines actually work. In fact, she only needed to try two number combinations in order to discover this.

*Which of the following combinations did she use to prove none of the machines work?*

a. 1, 2, 4, 3 and 2, 3, 4, 1

b. 2, 1, 3, 4 and 2, 3, 4, 1

c. 1, 4, 2, 3 and 2, 3, 4, 1

d. 1, 4, 2, 3 and 4, 1, 2, 3