A map 40 cm wide and 20 cm high is folded along the dashed lines to form a 10 cm by 10 cm square that just fits its envelope. It is then pinned to a notice board. Which pattern A–E could show the pinholes on the unfolded map?
Six people stand in a line. The first is 150 cm tall and the sixth is 180 cm tall. Every other person has height equal to the average of the heights directly in front and behind. How tall is the fourth person?
A tower uses 1 cube in its bottom layer, then 4 in the second, 9 in the third, then 16, and so on. It contains 91 cubes altogether. How many layers does it have?
A school places 76 students as evenly as possible into six classes, with any two class sizes differing by at most one. How many classes have exactly 12 students?
Four equal equilateral triangles with horizontal bases are arranged inside a larger equilateral triangle as shown. What fraction of the larger triangle is covered?
Anne has four cards, each with a different number. She lists all different totals obtained by choosing two or more cards and adding their numbers. What is the maximum number of different totals?
In March, April and May, my lawn grows 0.7 cm daily. On the day it reaches 20 cm I mow it back to 2.5 cm. If I mow on 1 March, how many mowings are needed in these three months altogether?
There are $n$ people equally spaced around a circle, numbered in order from 1 to $n$. Person 31 notices that people 7 and 14 are equally distant from him. How many people are there?