If a rectangle's area is 36 cm² and its length is 9 cm, what is its width?

To determine the width of the rectangle, we can use the formula for the area of a rectangle, which is Area = Length × Width. In this case, we know the area is 36 cm² and the length is 9 cm.

We can rearrange the formula to find the width:

Width = Area / Length

Substituting the known values:

Width = 36 cm² / 9 cm

Now, performing the division:

Width = 4 cm

Thus, the width of the rectangle is 4 cm, which corresponds to the chosen answer. This calculation shows a clear application of the area formula, reinforcing the concept that area is the product of length and width.