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

The gradient is a measure of how steep a line is.  It is calculated by finding the rate of change in the y-direction with respect to the positive x-direction

An intercept is the point where a line or curve meets a given axis

Checking and securing understanding of direct proportion graphs

Maths

Checking and securing understanding of inverse proportion graphs

In the linear graphs unit, pupils learnt to recognise and interpret graphs that illustrate direct and inverse proportion. In this unit, pupils learn how to represent these relationships algebraically.

In this unit, pupils learn how to represent direct and inverse proportion algebraically as an extension of work done in the linear graphs unit.

Direct and inverse proportion

If two variables have a constant multiplicative relationship, they are in {{ }} proportion.

Which of the following tables show values of A and B in direct proportion?

Which of the following graphs show direct proportion?

Calculate the value of k (constant of proportionality).

The {{ }} is the measure of how steep a line is.

Match each to the missing number that would replace the question mark.

The cost of 3 apples is  £1.59.  What is the cost of 36 apples?

The exchange rate is £1 : €1.18.  How many Euros would you get if you exchanged £300?

Using the exchange rate £1 : $1.27.  Which of the following are true?

A recipe says that you need 330 g of butter to make 30 cookies.  How much butter do you need to make 255 cookies?

Checking and securing understanding of direct proportion graphs

Lesson outcome