The average single woman does this every two-and-a-half weeks, while the typical single man does it once every three months. What is it?

The average single woman does this every two-and-a-half weeks, while the typical single man does it once every three months. What is it?

The average single woman does this every two-and-a-half weeks, while the typical single man does it once every three months. What is it?

Ans: Change their bed sheets.