As a review from the lesson on calculating unit prices, we must divide the cost of the item by the number of units of measure.

Now we can compare unit prices of two or more products.

Which is the better buy?
A 24 oz box of cereal for $3.69 or a 36 oz box of cereal for $4.89?

We must solve two division problems...

$3.69 24 ≈ $0.15

$4.89 36 ≈ $0.14

Which is the better buy?
A 18 oz jar of jam that costs $1.99 or a 24 oz jar of jam that costs $2.29?

$1.99 18 ≈ $0.11

$2.29 24 ≈ $0.10

 

Often it is necessary to use 0.5 when comparing unit prices, especially when the unit prices are similar ($0.12 vs. $0.125).  Sometimes a half cent makes the difference in a bargain!

 

Let's practice comparing unit prices.

 

 
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