Answer:
c. 50
Step-by-step explanation:
count each full block and every block that is more than half full as 1 each, ignore every block that is less than half full.
I got exactly 50 using this method before looking at the available answers.
In multiple choice math problems try to ignore the possible answers until you have determined what you think it ought to be. If the answer you found is in the list you have more confidence you are right, if the answer you got is not in the list you know you did something wrong... just a hint :)
Let's put it this way.
It's a ratio of 6:72 and we need to change it in a way to find number of rooms cleaned in 9 days.
Divide 6 & 72 both by 2
Ratio is now 3:36
Multiply 3 & 36 both by 3
Ratio is now 9:108
The number of rooms in which Robin can clean in 9 days is 108 rooms.
The slope of the line is positive
(2,-1) The intersecting point is the point where the two lines meet.