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.
