Back in the day of analog recording tape, Amalgamated Colgate Enterprises had a sale. Professional quality tape dropped from $30 to$28 per reel, and regular quality tape dropped from $24 to $23 per reel. The Bethel Recording Studio normally spent $1440 per week on tape, of which was used for professional quality tape. How much did they save during each week of the sale?
Solution
Bethel Recording studio normally spent of $1440, or $1080, per week on professional quality tape. At $30 per reel, they bought 36 reels per week. They spent the remaining $360 on 15 regular quality reels per week. Since they saved $2 per reel on the professional quality tape and $1 per reel on regular quality tape, they saved per week during the sale.
(Colgate Enterprises, so named, is in homage to Colgate toothpaste, which, in a great innovation back in the day, put the opening of its toothpaste tubes as tiny slits – rectangles if you will – rather than round holes. Their commercial went "Comes out like a ribbon, lies flat on the brush." The toothpaste was withdrawn from the market in 1979 but was reintroduced later and apparently is a best-seller in Turkey. The Wikipedia article does not mention how it now comes out of the tube.)