Suppose a designer has a palette of 8 colors to work with, and wants to design a flag with 2 vertical stripes, all different colors.

HOw many possible flags can be created?

For a flag with 2 different colours, there are 8 possible colours for the first colour to be chosen from and 7 possible colours (excluding the first colour already chosen) for the second colour to be chosen from, given that colours are different. Hence there are a total of 8 x 7 = 56 possible flags to be created.