Manufacturers will often provide after-purchase rebates to consumers who purchase their product from a retailer as an incentive for consumers to buy their products over competitors products.

House Depot, a large home improvement retailer, has several manufacturer rebate promotions on popular home improvement products during the month of July. In order to qualify for the rebates, one must purchase at least the minimum dollar amount for each product according to the table below.

House Depot Manufacturer Rebates on Select Products

 Floor TilesPaintWallpaper
Over $100$20$15$35
Price List for House Depot Home Improvement Products

Lavertine Tiles1 sq. ft. each
16 per pack
Trinoleum Tiles0.5 sq. ft. each
16 per pack
Magic Color Paint32 sq. ft. worth
per can
Rainbow Wallpaper16 sq. ft. per sheet
10 sheets per pack
Cloud Wallpaper10 sq. ft. per sheet
8 sheets per pack
Packaged products cannot be split into individual products.

Installing Cloud Wallpaper

Lavertine Tiles and one coat of Magic Color Paint

Two coats of Magic Color Paint

Trinoleum Tiles and Rainbow Wallpaper

Trinoleum Tiles and one coat of Magic Color Paint

On a question like this, the calculator function is likely a combination of tempting and comforting. But beware -- in a timed situation, and with a primitive calculator at your disposal, performing unnecessary calculations can still take valuable time and increase the possibility for error. Knowing that your job is to find the least expensive option, you should use a "tournament style" process of elimination, only making calculations when you feel that the results will be close.

First, consider the relative amounts of product needed for floor and wall coverings. There are two walls that run 9x6 (54 square feet) and two that run 9x8 (72 square feet) for a total of 252 square feet required. For the floor, the dimensions are 6x8 = 48 square feet.

To cover the walls with Cloud Wallpaper, you need 252 square feet, which means that you'll need to purchase 4 packs of wallpaper (you can't quite accomplish it with 3, which at 10 feet/sheet and 8 sheets/pack would only give you 3*80 = 240 square feet). 4 at $32 each will come out to $128, but with the $35 rebate for spending more than $100 on wallpaper the total price will be $93.

With $93 as the current "leader", try choice B. Note first that there are two components, and that the larger component is the wall so you'll likely want to see if you can keep the wall cost under $93 first before adding in the floor, only if necessary. A glance at the table shows that paint runs for $25 per 32 square feet -- much, much higher than the $32 per 80 square feet we encountered with wallpaper. And with only a $15 rebate on paint (compared to the $35 we got on wallpaper), paint will not be less expensive than wallpaper. We can eliminate all three paint choices, B, C, and E.

Now we simply need to compare D to the current-leader $93 (from A). Rainbow Wallpaper, through a quick glance, is less than half the price of Cloud Wallpaper, so this math is worth doing. We'll need 2 packs (at 160 feet per pack) at $30/each. So wallpaper will cost $60, with a $20 rebate for an out-the-door total of $40. Because this is so low, it makes sense to continue working through this answer choice by assessing the Trinoleum Tiles. We need 48 square feet's worth, and at 8 square feet per pack (1/2 foot per tile, 16 tiles per pack) we need 6 packs. The packs cost $10/each, so we need to spend $60, and we'll receive a $10 rebate. So the total tile cost is $50 to add to the $40 we spend on wallpaper for a $90 total, just under the $93 cost from choice A. D is the correct answer.