In order to find the best deal on many products it is necessary to shop around. If you are looking for a TV you check a few stores and see if they have different prices, but what if you are looking at the same thing in the same store in different quantities. This is much harder than looking at TV's. An example of this is flour, a 500g bag of flour costs $1.29 and a 750g bag costs $1.55. It is obvious the larger bag costs more, because of the price. However, you are also getting more product in the larger bag. For example: Coffee Total Price Total Units Unit Price = So we need a way to compare the cost of objects that are different sizes. We call this unit cost as we are comparing items that are measured in different unit sizes. It is working with rates. Find the best deal for coffee. Deal #1 Deal #2 Deal #3 150g at $3.69 225g at $5.49 200g at $4.49 In order to find the unit cost we usually convert the dollar amount into cents, so $6.79 would be 679 cents. 3 Deal #1 Unit cost Deal #2 Unit cost Deal #3 Unit cost = price amount 369 150 = 2.46 cents per gram I price amount 549 225 = 2.44 cents per gram price amount Unit cost 449 200 = 2.50 cents per gram This shows that our best deal when it comes to unit price is deal #2. 1. Using unit cost which of the following is the best deal? Express the answers to the nearest cent as a unit cost. 4L of milk at $3.99 11 = price amount 3 1L of milk at $1.49 Unit cost 3L of milk at $3.39 Unit cost a) What are the advantages of each size? b) Why might someone buy the larger size? c) Why might someone buy the smallest size?