# Inverse proportion

## Switch to our new maths teaching resources

Slide decks, worksheets, quizzes and lesson planning guidance designed for your classroom.

## Lesson details

### Key learning points

1. In this lesson, we will explore when two quantities are inversely proportional to each other. We will learn about the term inverse proportion and how to identify an inversely proportional relationship.

### Licence

This content is made available by Oak National Academy Limited and its partners and licensed under Oak’s terms & conditions (Collection 1), except where otherwise stated.

## Video

Share with pupils

## Worksheet

Share with pupils

## Starter quiz

Share with pupils

### 5 Questions

Q1.
1 bar of chocolate costs £2.10. How much do 3 bars of chocolate cost?
£3.60
630
Q2.
Four tickets to the cinema cost £42. How much do 8 tickets cost?
£168
£336
Q3.
Four tickets to the cinema cost £42. How much do 9 tickets cost?
£105
£159
Q4.
Fill in the gaps: You can use .............. .............. to work out the best value for money.
inverse proportion
shop offers
Q5.
x and y are directly proportional. What happens to y if x doubles?
+2
half

## Exit quiz

Share with pupils

### 5 Questions

Q1.
Fill in the gaps: Two quantities a and b are said to be directly proportional if one quantity is always a constant ........ of the other.
factor
prime
Q2.
Fill in the gaps: Two quantities x and y are said to be inversely proportional if x increases as y ............... at the same rate, so their product is constant.
increases
stays the same
Q3.
Fill in the gaps: Two variable quantities are said to be ........................ proportional if the product of the two quantities is constant.
constantly
directly
Q4.
Three builders take 15 days to complete a project. How many days does would it take one builder?
30 days