Question bank BEBRAS 2026

Look at the sequence and choose the shape that belongs at the question mark.

The beaver has four boxes, each containing a different type of decorative lamp, as shown. In the table, Hộp means Box and Loại đèn means Lamp type.



The beaver takes lamps from boxes C, A, D and B in that order and joins them into a string in the same order. Which string is made?

The beavers name shapes according to this table. Hình means Shape and Cách gọi means Name.



One beaver names a sequence of shapes as shown below.



How many naming mistakes are there?

Mai has four pots of flowers as shown: Tuy-líp = tulips, Oải hương = lavender, Cúc = daisies and Mẫu đơn = peonies. She wants to give her father 1 peony, 1 tulip and 3 daisies.



After the gift, which pot has the most flowers left?

The beaver cuts a circular piece from this card.



Which piece below CANNOT be the piece that was cut out?

Cars from two branches A and B want to enter the main road C. They enter alternately from A, B, A, B, A, B, and so on, beginning with car 6, then car 5.



Which car enters road C immediately after car 9?

Consider this door. The labels Khe cửa and Tay nắm cửa identify the window opening and the handle.



Two doors are completely different if all four features differ: the door’s shape, color, window shape and handle shape. How many doors below are completely different from the given door?

Four baskets contain balls as shown.



Việt moves balls from one basket to another, one ball per move. What is the fewest moves needed to make all four baskets contain the same number of balls?

The robot wants to reach the ball (the circle). On each step it may move up, down, left or right. It may not move diagonally or enter a black square.



What is the smallest number of squares it must pass through, excluding the first and last squares?

Five otters swim down a river holding hands in a horizontal line. At each river fork, two neighboring otters let go to split the line into two groups. Each group swims into a different branch.



Each otter wants to reach the house with the same letter as its name. Which two otters must let go at the first fork?

Mai and Nam have a board of 12 squares. A square touched by Mai has vertical lines:



A square touched by Nam has horizontal lines:



A square touched by both has diagonal lines:



After they touch the squares, the board looks like this. How many squares did Mai touch?

The village has 18 houses as shown. If two houses are joined by a road, travelling between them takes 1 minute.



How many houses can reach house J in no more than 2 minutes?

Editorial counting convention: count houses other than J itself.

The beaver has a cube whose six faces contain the pictures shown.



These are two photographs of the cube.



Which picture is on the face opposite the beaver picture?

Seven planes are queuing to enter the runway and take off as shown. Đường băng means Runway.



Their departure times are in the table, with some entries missing. Thời gian means Time and Máy bay means Plane.



Which plane takes off at 12:00?

An and Bin are going home from the forest. Some direction signs have gone missing. The map labels their homes and starting positions; Dòng sông means River.



They follow these rules:
- Travel only along the grid lines.
- Start in the direction of the first large black arrow.
- Continue straight until reaching another arrow, then follow its direction. Repeat until home.
They cannot swim across the river and must use one of the two bridges.

How many ways can one right-pointing arrow and two upward-pointing arrows be added so that both An and Bin reach their own homes?

Editorial placement clarification: put the new arrows at unused marked intersections; keep the printed arrows and starting positions unchanged.

The beaver uses two balls of yarn to knit one shirt, or one ball to knit one scarf, as shown.



With two blue balls and four yellow balls of yarn, which set of products can the beaver make?

Sticky rice cake is often cut with strings rather than a knife because the cake is sticky. These pictures show one-string cutting.



Several strings may also be used, but must be pulled in the right order so they do not catch on each other. In the two-string example, pull the white string before the grey string; reversing that order traps the grey string.



In what order should the four strings below be pulled?

Alice and Bob are spies. They use the alphabet ABCDEFGHIJKLMNOPQRSTUVWXYZ and encrypt each letter by replacing it with the next letter; Z becomes A. The examples are HELLO→IFMMP and CALL ZARA→DBMM ABSB.



Bob wants to send CHOCOLATE. Which encrypted message should he send?

The map shows beaver cities and bus links. Each number is the fare for travelling along that link.



What is the least total fare for travelling from city A to city F?

A robot embroiders carpets using four coded patterns: 00 horizontal lines, 11 dots, 01 diagonal lines, 10 vertical lines.



It follows each row from left to right, and rows from top to bottom. The program is:
- Row 1: 00-10-10-10-01-10-10-10-00
- Row 2: 10-01-10-01-01-01-10-01-10
- Row 3: 01-11-01-01-11-01-01-11-01
- Row 4: 10-01-10-01-01-01-10-01-10
- Row 5: 00-10-10-10-01-10-10-10-00

Which carpet results?