Question

In how many ways one can post three letters in four letter boxes?

• A. $3^4$
• B. $3^3\times 4$
• C. $4^3$
• D. $3\times 4^3$

Answer 1

The correct option is C $4^3$

Let L1, L2, L3 and L4 be four letter boxes,
now we have three letters and the letter boxes present is four.
A letter could be placed in any of four diffrent boxes, thus there are four ways to place a single letter. Similarly there are 4 ways each for three different letters
Hence, the total number of ways=$4\times 4\times 4=4^3$