California Assessment of Student Performance and Progress (CAASPP) Math Practice Exam 2026 - Free CAASPP Math Practice Questions and Study Guide

To find the perimeter of a rectangle, you can use the formula:

Perimeter = 2 × (Length + Width).

In this case, the length of the rectangle is 8 cm and the width is 5 cm. First, add the length and the width together:

8 cm + 5 cm = 13 cm.

Next, multiply this sum by 2 to find the perimeter:

2 × 13 cm = 26 cm.

Therefore, the perimeter of the rectangle is 26 cm, which corresponds to the correct answer. This method ensures that the perimeter accurately reflects the distance around the rectangle.