Can you make a tetrahedron whose faces all have the same perimeter?
A group of 20 people pay a total of £20 to see an exhibition. The admission price is £3 for men, £2 for women and 50p for children. How many men, women and children are there in the group?
Show that for any triangle it is always possible to construct 3 touching circles with centres at the vertices. Is it possible to construct touching circles centred at the vertices of any polygon?
What can you deduce by comparing the bottom two rows?
If you could work out the value of the square, how could you then work out the value of the triangle?