Question

I have counters of $n$ different colours, red, white, blue,...; in how many ways can I make an arrangement consisting of $r$ counters, supporting that there are atleast $r$ of each different colour?

• A. $r^n$
• B. $r^r$
• C. $n^r$
• D. None of the above

Answer 1

The correct option is B $r^r$

We have $n$ different colour. and for each colour have $r$ different choices.

So we have $r\times r\times r\times r\times r............ntimes$= $r^n$