# There are 6 balls, all uniquely coloured, in a bag. We're randomly drawing 2. How many ways can we draw first Blue, then White? How many ways can we draw the colour combination of Blue and White?

##### 1 Answer

Mar 14, 2017

#### Explanation:

We have 6 marbles and are pulling out 2.

The first question asks about colour sequences (and so Blue, White is different than White, Blue) and so is a permutation. The general formula is:

The second part of the question asks about colour combinations, and so Blue, White is the same as White, Blue. That is a combination and the general formula is: