Praxis Core Academic Skills for Educators: Mathematics (5733)GeometryHard

A manufacturer is designing a new packaging box for a product. The box needs to be a rectangular prism with dimensions of 6 inches by 4 inches by 3 inches. If the box is to be covered entirely with a decorative paper, what is the total surface area of the box that needs to be covered?

  1. A74 square inches
  2. B148 square inches
  3. C108 square inches
  4. D72 square inches
Show answer & explanation

Correct answer: B. 148 square inches

The surface area of a rectangular prism is given by the formula SA = 2(lw + lh + wh), where l is length, w is width, and h is height. This represents the sum of the areas of all six faces of the prism.

Why the other options are wrong

  • A. This is incorrect; it might be the sum of only three faces or a miscalculation.
  • C. This is incorrect; it might be a result of adding dimensions or an incorrect formula application.
  • D. This is incorrect; it is the volume of the box, not the surface area.

Surface Area of Rectangular Prism

The total area of all the faces (surfaces) of a three-dimensional rectangular prism.

  • A rectangular prism has 6 faces (3 pairs of identical rectangular faces).
  • Formula: SA = 2(lw + lh + wh).
  • Where l=length, w=width, h=height.

Memory trick: Surface Area: 'Two' of 'Length-Width', 'Length-Height', and 'Width-Height'!

More Geometry questions