Given:
Reservation fee = $19
Additional fee = $6 per hour
The chemistry club wants to spend at most $19 on renting the room.
To find:
The possible numbers of hours the chemistry club could rent the meeting room.
Solution:
Let n be the number of hours the chemistry club could rent the meeting room.
Reservation fee = $19
Additional fee for one hour = $6
Additional fee for n hours = $6n
Total fee = $(6n+19).
The chemistry club wants to spend at most $19 on renting the room. It means the total fee must be less than or equal to 19.

Subtract 19 from both sides.

Divide both sides by 6.

Time can not be negative. So n=0.
Therefore, the possible numbers of hours the chemistry club could rent the meeting room is 0.