A compound shape is made up of two or more shapes.

A dimension is a measurement of length in one direction. Width and height are examples of the dimensions of 2D shapes.

Calculate missing dimensions in rectangles and compound rectilinear shapes

Maths

In this unit pupils will calculate the area of a rectangle using multiplication and use their knowledge of area to solve problems. In the future unit pupils will explain what volume is using a range of contexts and describe the units used to measure volume. They will explain how to calculate the volume of a cuboid.

In the prior unit pupils explained area and measured using counting as a strategy. They made different shapes with the same area and compared the area of different shapes. In this unit pupils will calculate the area of a rectangle using multiplication and use their knowledge of area to solve problems.

Link area of rectangles to multiplication

The area of this compound shape is 116 cm². What is the missing dimension? 


Here is a shape made from three identical rectangles. The area of the shape is 180 cm². What are the missing dimensions? 

The larger blue rectangles are double the area of the smaller red rectangles. Calculate the area of a small red rectangle.

Which of these compound rectilinear shapes have a total area of 60 m²?

Which calculation would you use to calculate the area with the information you have been given?

Jun worked out the area of a compound shape. Which of these shapes was he calculating the area of?

What is the area of the grey path around the pond?


This lesson will soon be taken down.

Calculate missing dimensions in rectangles and compound rectilinear shapes

Lesson outcome