114/6=9 parts per minute. 9 parts * 15 minutes= 135 parts
Consequently, the equation determining the remaining number of rooms Martin has to clean after
hours can be represented as: 
, in which 
indicates the overall number of rooms. Step-by-step explanation: It is given that Martin has 4 rooms left to clean and takes 7 hours for the task. The equation in standard form for the number of rooms remaining after x hours, y, is set up as follows: The remaining rooms 
, indicates the quantity after 
hours. The cleaning rate is established as follows: Considering Martin cleans 4 rooms in 7 hours, the rate at which he cleans is given by: Hence, the equation can be expressed as
(Answer)
.
