Answer:
18 days
Explanation:
To determine the fewest number of days that will pass before both rooms are cleaned again on the same day, we list the multiple of each of the days.
[tex]\begin{gathered} 6=6,12,18,24,30,36,42,48\ldots \\ 9=9,18,27,36,45,54,\ldots \end{gathered}[/tex]The next multiple 6 and 9 have in common is 18.
Therefore, after 18 days has passed, the two rooms will be cleaned on the same day.
