GED Mathematical Reasoning Practice Questions: Squares, Roots, and Cubes

On the Mathematical Reasoning section of the GED, certain problems require that you know how to determine a value’s square or square root, or its cube or cube root.

You’re not likely to encounter problems that only involve squares and cubes. Instead, they’ll appear as word problems, as in the following examples.

Practice questions

  1. George is framing several square pictures, two of which measure 8 inches by 8 inches and the third of which measures 7 inches by 7 inches. How many square inches of glass would he need to exactly cover the pictures before putting them in frames?

    A. 128

    B. 177

    C. 49

    D. 113

  2. A cubic box holds 4,320 jelly beans. If there are 20 jelly beans per cubic centimeter, what is the length of one side of the box?

    E. 5.0

    F. 5.5

    G. 6.0

    H. 6.5

Answers and explanations

  1. B.

    Two of the pictures measure 8 inches by 8 inches, so they would require

    two times eight squared equals one hundred twenty eight.

    square inches of glass. The third one would require

    seven times seven equals forty nine.

    square inches of glass. In total, George would need 128 + 49 = 177 square inches of glass.

  2. G.

    First divide the total number of jelly beans in the box by 20 jelly beans per cubic centimeter to determine the volume of the box in cubic centimeters, which comes to 216. One side of the cube is

    The cube root of 216 is six.

    Choice (G) is the correct answer.