# Question Video: Recognizing the Perimeters of Rectangles with Equal Areas Mathematics • 3rd Grade

Here are two rectangles with the same area. Which of them has the largest perimeter?

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### Video Transcript

Here are two rectangles with the same area. Which of them has the largest perimeter?

In this question, we’re being asked to compare the perimeter of two shapes which have the same area. Let’s calculate the perimeter of our first shape. Perimeter is the distance around the shape. To calculate perimeter, we need to add together the length of all the sides. We can use the squares to help us. The shape is two centimeters wide and eight centimeters long. So to calculate the perimeter of this shape, we need to add together eight plus eight plus two plus two centimeters. Two lots of eight or double eight is 16 and double two is four. 16 plus four is 20, so the perimeter of our first shape is 20 centimeters.

The second shape measures three centimeters by four centimeters. So to calculate the perimeter, we need to add three centimeters plus three centimeters plus four centimeters plus four centimeters. We know that double three is six and double four is eight. Six plus eight gives us a perimeter of 14 centimeters. 20 is greater than 14. So this is the rectangle with the largest perimeter.