Being resourceful

Can you find the values at the vertices when you know the values on the edges of these multiplication arithmagons?

Can you explain what is going on in these puzzling number tricks?

Can you create a Latin Square from multiples of a six digit number?

A 2-digit number is squared. When this 2-digit number is reversed and squared, the difference between the squares is also a square. What is the 2-digit number?

Which has the greatest area, a circle or a square, inscribed in an isosceles right angle triangle?

A napkin is folded so that a corner coincides with the midpoint of an opposite edge. Investigate the three triangles formed.

A hexagon, with sides alternately a and b units in length, is inscribed in a circle. How big is the radius of the circle?

An observer is on top of a lighthouse. How far from the foot of the lighthouse is the horizon that the observer can see?

If a sum invested gains 10% each year how long before it has doubled its value?

Explore the relationships between different paper sizes.