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Home > PC > Chapter 9 > Lesson 9.1.1 > Problem 9-11

  1. Suppose you want to buy rice. Different size packages cost different amounts, but the relationship is not always linear. That is, a bag twice as big does not usually cost twice as much. The chart shows the prices for various sizes of bags of rice. Homework Help ✎

    1/2 lb bag


    1 lb bag


    2 lb bag


    5 lb bag


    10 lb bag


    20 lb bag


    1. Find the rates in cost per pound. (Stores refer to this as unit pricing.)

    2. Does the unit price increase or decrease with the size of the bag?

    3. Does the rate change more drastically for smaller sizes or for larger sizes?

Divide the cost by the pounds for each row.

The unit price decreases as the size of the bag decreases.

The rate change is more drastic in the smaller sizes. Note: Sketching a graph of rate with respect to bag size may help here.