SOLUTION: Suppose that a gallon of wall paint costs $40 and covers 150 sq ft. Three rooms of the house measure 10 ft by 12 ft, 12 ft by 14 ft and 12 ft by 16 ft. The ceiling is 11 ft high.

Algebra ->  Formulas -> SOLUTION: Suppose that a gallon of wall paint costs $40 and covers 150 sq ft. Three rooms of the house measure 10 ft by 12 ft, 12 ft by 14 ft and 12 ft by 16 ft. The ceiling is 11 ft high.      Log On


   



Question 110034: Suppose that a gallon of wall paint costs $40 and covers 150 sq ft. Three rooms of the house measure 10 ft by 12 ft, 12 ft by 14 ft and 12 ft by 16 ft. The ceiling is 11 ft high. Use this information and equations and formulass to answer the first 4 questions.
How many gallons of paint are needed to cover the wall of these rooms if you make no allowance for the doors and windows?
Just the walls not the ceilings?
Round up to next gallon since can't buy part of a gallon.

Answer by josmiceli(19441) About Me  (Show Source):
You can put this solution on YOUR website!
Find total area of the rooms
A+=+l%2Aw%2Ah
for the 1st room
A%5B1%5D+=+2%2A11%2A10+%2B+2%2A11%2A12
2nd room
A%5B2%5D+=+2%2A11%2A12+%2B+2%2A11%2A14
3rd room
A%5B3%5D+=+2%2A11%2A12+%2B+2%2A11%2A16
The 2's are need because opposite walls are the same area
The 11's mean all the heights are the same
Find A%5B1%5D+%2B+A%5B2%5D+%2B+A%5B3%5D
2%2A11%2A10+%2B+2%2A11%2A12+%2B++2%2A11%2A12+%2B+2%2A11%2A14+%2B+2%2A11%2A12+%2B+2%2A11%2A16
Now factor out 11's and 2's
2%2A11%2810+%2B+12+%2B+12+%2B+14+%2B+12+%2B+16%29
2%2A11%2810+%2B+36+%2B+14+%2B+16%29
2%2A11%2A76
A+=+1672 ft2
A gallon of paint covers 150 ft2
G = gallons needed
G+=+1672+%2F+150
G+=+11.15 and since I can't buy part of a gallon,
I need 12 gallons of paint