Part 1: Follow along with your instructor to complete this lesson. A. A third model of subtraction is to use a part/part/whole relationship. A number can be broken apart into smaller parts, as shown below. If you add the smaller parts back together, you end up with the whole thing. B. The whole figure below has 9 units. The first part has 5 units. Label the figure with these two values. Now, find the missing part. (Count up to find the difference, just like in the previous lessons). Part 2: Find the missing part. (Count up to find the difference). Part 3: Find the missing parts in Column 1. Then, solve the related subtraction problems in Column 2.
Worksheets teach to subtract