A cube is to be coloured in such a way that no two opposite faces have the same colour, then the minimum number of colours reuired is

Study the figure given below to answer the questions that follow. If all the independent triangles in the above figure where coloured in such a way that two nearby triangles with a common side will not be of the same colour. What is the minimum number of colours required?

If each of the six squares in the strip shown in figure is to be colouredwith any one of ten different colours so that no two adjacent squareshave the same colour,then the number of ways of colouring the strip is

Which of the following pair of ions have the same colour ?

Each of the six squares in the strip shown in the fig., is to be coloured with anyone of ten different colours so that no two adjacent squares have the same colour. Find the number of ways of colouring the strip.

A big cube is formed by arraning the 160 coloured and 56 noncoloured similar cubes in such a way that the exposure of the coloured cubes to the outside is minimum. The percentage of exposed area that is coloured is