ASVAB Mathematics Knowledge Practice: Surface Area

By Consumer Dummies

Just as there are different sides to every story, there are also different sides to every three-dimensional object. Some questions on the Mathematics Knowledge subtest on the ASVAB will ask you to add up all the sides of a figure to find its total surface area.

Practice questions

  1. Find the surface area:

    asvab-surface-area

    A. 48 square yards
    B. 72 square yards
    C. 90 square yards
    D. 96 square yards

  2. Find the surface area:

    asvab-surface-radius

    A. 2,800 cm2
    B. 2,820 cm2
    C. 2,826 cm2
    D. 2,152 cm2

Answers and explanations

  1. The correct answer is Choice (D).

    The formula to find the surface area of a prism is SA = 2B + Ph, where B represents the area of the base, P represents the perimeter of the base, and h represents the height of the prism.

    First find the area of the triangular base using

    ASVAB_2001

    where b represents the triangle’s base and h represents its height:

    ASVAB_2002

    Find its perimeter by adding the length of each leg:

    6 + 8 + 10 = 24

    The base’s area is 24 square yards, the base’s perimeter is 24 yards, and the prism’s height is 2 yards, so plug that information into the formula for the surface area of a prism:

    SA = 2(24) + 24(2)

    SA = 48 + 48

    SA = 96

    The surface area of the prism is 96 square yards.

  2. The correct answer is Choice (C).

    The formula to find the surface area of a sphere is

    ASVAB_2003

    so use the values you know to solve the problem:

    ASVAB_2004