SOLUTION: A building is 6 stories tall with windows on all 4 sides. Each floor has 24 windows. Each spring, all the windows are washed. The cost for washing the windows is $1.00 for each 1st

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Question 526267: A building is 6 stories tall with windows on all 4 sides. Each floor has 24 windows. Each spring, all the windows are washed. The cost for washing the windows is $1.00 for each 1st floor window, $1.50 for each 2nd floor window, $2.00 for each 3rd floor window and so on. How much would it cost to wash the windows in the building if it were 20 stories tall? What if it were n stories tall?
I understand how to find the cost for 20 stories, but not n stories.
Answer by scott8148(6628) About Me  (Show Source):
You can put this solution on YOUR website!
the cost for a window is ___ .50 + .50f , where f is the floor

the average cost per window for n stories (floors) is ___ [(1st floor) + (nth floor)] / 2

the total cost for n stories is 24n times the average ___ 24n[1 + (.50 + .50n)] / 2

12n(1.50 + .50n) ___ 18n + 6n^2