Use these four dominoes to make a square that has the same number of dots on each side.
I want some cubes painted with three blue faces and three red faces. How many different cubes can be painted like that?
Charlie has moved between countries and the average income of both has increased. How can this be so?
A walk is made up of diagonal steps from left to right, starting at the origin and ending on the x-axis. How many paths are there for 4 steps, for 6 steps, for 8 steps?
It is impossible to trisect an angle using only ruler and compasses but it can be done using a carpenter's square.
Can you rearrange the cards to make a series of correct mathematical statements?
Relate these algebraic expressions to geometrical diagrams.
This is a beautiful result involving a parabola and parallels.
Can you invert the logic to prove these statements?
Can you work through these direct proofs, using our interactive proof sorters?