Question

In how many ways can $mn$ letters be posted in $n$ letter-boxes.

• A. $(mn)^{n}$
• B. $m^{mn}$
• C. $n^{mn}$
• D. None of these

Answer 1

Answer: (C)

$n^{mn}$

Answer 2

Required number of ways are $n^{mn}$ since each letter may be posted in $n$ ways.