Two variables are in direct proportion if they have a constant multiplicative relationship.

Checking and securing understanding of direct proportion in context

Maths

In the prior unit, pupils enhanced their understanding of enlargement. In this unit, pupils investigate the effect of an enlargement on the perimeter and area of a 2-D shape and the volume of a 3-D shape.

Similarity

Two variables are in direct proportion if they have a __________ relationship.

Which of these graphs shows direct proportion between the two variables?

The ratio table shows the conversion €7 (Euros) = £6 (Pounds Sterling).  €630 = £{{ }} 

The perimeter of a triangle is 33 300 cm. Which calculation shows its perimeter in metres?

The arc length is directly proportional to the radius.

The area is directly proportional to the radius.

If the radius is doubled, the arc length will be 4π cm

If the radius is doubled, the area will be 12π cm².

A circular sector with an angle of 60° has a radius of 6 cm, an arc length of 2π cm and an area of 6π cm².  Select the correct statements.

The area of a triangle is 600 cm². The area of the triangle in metres squared is {{ }} m².

Two variables are in {{}} proportion if they have a constant multiplicative relationship. 

Four friends went to the cinema. The cost of their tickets was £38. How much did each ticket cost? £{{}}

In a supermarket, 3 tins of soup cost £4.80. 8 tins of the same soup should cost £{{ }}

Match each measurement to its equivalent measurement.

Calculate the surface area of this cuboid.

This lesson will soon be taken down.

Checking and securing understanding of direct proportion in context

Lesson outcome