Kirsten joins the even-numbered points to make one triangle and the odd-numbered points to make another. She colours one triangle red and the other green. Which option shows her picture?
Cistercian numerals were used in the early thirteenth century. A number from 1 to 99 is written by combining the appropriate unit and tens glyphs shown. Examples for 24, 81 and 93 are also shown. Which glyph represents 45?
Vehicles in the garage may move forward or backward but cannot turn. What is the smallest number of vehicles that must move to make it possible for the black car to leave?
Five big elephants and four small elephants walk along the path in the order shown. At the junction each turns left or right. Which situation cannot occur after all have passed?
A rectangular tank measures 1 m by 2 m by 4 m. Initially its base is 4 m by 2 m and the water is 25 cm deep. It is turned so the 1 m by 2 m face is the base. What is the new water depth?
The transparent paper has the design shown. It is folded twice along the dashed lines in the indicated directions. What will be seen on the folded paper?
2022 is special because the digit 2 occurs three times. This is the third year with three identical digits that Eva the tortoise has lived through. What is the youngest she could be by the end of 2022?
Jessi places 3, 4, 5, 6, 7, 8 and 9 in the seven circles so that the three numbers on each straight arm have the same sum. What is the largest possible common sum?