Solving for a Missing Dimension

Locating the 3rd Dimension

The GED tends towards complex problems. Don't be surprised if the volume and surface area problems you get on your test require you to work backwards; they give you the surface area or volume and expect you to solve for a missing dimension.

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To solve for a missing dimension:

  • Locate the appropriate formula from the GED formula sheet

  • Substitute any known values into the formula

  • Use your algebra skills to solve for the remaining variable

Watch the Virtual GED Class video below for a complete explanation and tons of worked example problems.


Solving for Missing Dimensions Beginner

Solve for a dimension when given perimeter or area

Utilizing Formulas Intermediate Level.docx

A mix of straightforward and trickier application problems

Utilizing Formulas GED Style Challenge Problems.docx

GED Style Formula Challenge Problems


Example 1

Example 2

Challenge 1

Challenge 2

Challenge 3

Example 3

Example 4

Example 5


Challenge 4

Challenge 5

Challenge 6

Challenge 7