Question

Find the number of ways in which 5 letters can be posted in 3 post boxes if any number of letters can be posted in a post box.

Answer 1

There are 5 letters and 3 post boxes and any number of letters can be posted in all of three post boxes.

∴ Each letter can be posted in 3 ways.

∴ Total number of ways 5 letters can be posted

= 3 × 3 × 3 × 3 × 3

= 243