Question 1141302
Light-at-Dawn: The regular price of a 1-gallon can is $24, but it is on sale for 25% off the regular price. This type of paint requires 2 coats.
Cloudy Sunrise: The price of a 1-gallon can is $28. This type of paint only requires 1 coat.
Each gallon a point will cover an area of about 350 square feet.


cost of 1 gallon of light at dawn color is equal to 24 minus .25 * 24 = 18.


cost of 1 gallon of cloudy sunrise color is equal to 28.


it looks cloudy sunrise color is more expensive until you take into account the square feet that each color can cover.


both cans are given as covering 350 square feet.


all other things being equal, .......


the cost of light at dawn color would be 18 / 350 = .0514285714 per square foot.


light at dawn color, however, requires two coats.


if the second coat takes as much paint as the first coat, then the total cost per square foot of light at dawn color would be 2 * .0514285714 = .1028571429.


the cost per square foot of cloudy sunrise is 28 / 350 = .08.


since cloudy sunrise color only requires one coat, then this is the total cost per square foot for cloudy sunrise color.


assuming that the second cost of light at dawn color requires the same amount of paint as the first coat, it appears that the total cost of cloudy sunrise color is less expensive than the total cost of light at dawn color.


you did not indicate in your problem the total length of the walls.


you only indicated the height of the walls and the number of windows in the room.


you also needed to indicate the square feet of the room so that the total length of the walls could be calculated.


without that, there's no way of knowing how many gallons of each paint would be required.


analyzing it on a cost per square foot basis, the cost for light at dawn color is clearly more expensive if we assume that the amount of paint required for the second coast is the same as the amount of paint required for the first coat.


in real life, the second coat doesn't normally require as much as the first coat because the first coat is absorbed into the surface of the walls while the second coat doesn't get absorbed as much.


but, that's real life, and this problem is not necessarily real life, so the assumption that the second coat requires as much paint as the first coat is reasonable.


analyzing on a cost per square foot basic doesn't take into account efficiency.


for example:


if the total square feet required to be covered is 175, then one can of light at dawn color would suffice for a total cost of 18 dollars.


you would still require to buy one can of cloudy sunrise color for 28 dollars, even though you only needed to use half the can.


unless you could use the cloudy sunrise paint left over for another project, then the cloudy sunrise paint wojld be more expensive.


on the other hand, if 350 square feet needed to be covered, you would require 2 cans of light at dawn color for a total of 36 dollars while only requiring one can of cloudy sunrise color for a total of 28 dollars.


in that scenario, the cost for light at down color would be more.


bottom line is you need to know the total square feet of the room to make this kind of determination.