• Mastery PD Materials

## Multiplicative contexts: area and perimeter 1

Spine 2: Multiplication and Division – Topic 2.16

### Introduction

Use addition and multiplication to solve problems about the perimeter of irregular and regular 2D shapes, and to find the area of rectilinear and composite rectilinear shapes; use division to solve associated inverse problems.

### Teaching points

• Teaching point 1: Perimeter is the distance around the edge of a two-dimensional (2D) shape.

• Teaching point 2: Perimeter is measured in units of length and can be calculated by adding together the lengths of the sides of a 2D shape.

• Teaching point 3: Multiplication can be used to calculate the perimeter of a regular polygon; when the perimeter is known, side-lengths can be calculated using division.

• Teaching point 4: Area is the measurement of the surface of a flat item.

• Teaching point 5: Area is measured in square units, such as square centimetres (cm2) and square metres (m2).

• Teaching point 6: The area of a rectangle can be calculated using multiplication; the area of a composite rectilinear shape can be found by splitting the shape into smaller rectangles.

• Primary
• KS2
• Year 4