A bus route has a total duration of 40 minutes. Every 10
minutes, two buses set out, one from each end. How many buses
will one bus meet on its way from one end to the other end? Two
engines, at opposite ends of a single track railway line, set
off towards one another just as a fly, sitting on the front of
one of the engines, sets off flying along the railway line...
Find a cuboid (with edges of integer values) that has a surface
area of exactly 100 square units. Is there more than one? Can
you find them all? This shape comprises four semi-circles. What
is the relationship between the area of the shaded region and
the area of the circle on AB as diameter? An irregular
tetrahedron has two opposite sides the same length a and the
line joining their midpoints is perpendicular to these two edges
and is of length b. What is the volume of the tetrahedron? If
the radius of the tubing used to make this stand is r cm, what
is the volume of tubing used? At least three ways to solve this
problem, but Charlie and Ian sho