Graduate Management Admission Test (GMAT) Practice Test

The area of a rectangle is calculated using the formula that involves multiplying its length by its width. This mathematical principle works because a rectangle is defined by its two dimensions: the length (the longer side) and the width (the shorter side). When you multiply these two dimensions together, you determine how much two-dimensional space the rectangle occupies, which is represented in square units.

Let's consider the other options to provide context. Adding the length and width does not give a meaningful measurement regarding area; instead, it results in a single dimension, which does not reflect the surface area. Subtracting the width from the length also does not yield a proper measurement of area, as it simply gives the difference between the two lengths. Dividing the length by the width calculates a ratio, which can provide information about the rectangle's proportions but not its area.

Therefore, the multiplication of length and width is the correct and appropriate procedure for finding the area of a rectangle, confirming that it is indeed the correct answer.