2. Rate a comparison of two differing quantities can be expressed as a fraction. e.g.Rate of travel 80km/h Fuel Consumption 7.3 L/100km Fuel Price 136.9 cents/Litre Pay Rate $18/h Ratio a comparison of two similar quantities. can be expressed as a fraction. order of numbers Proportion A statement of equality between two ratios. Can be direct – relation between the two variables remains constant i.e when one quantity increases, the other increases. Similarly when one quantity decreases, the other quantity decreases. OR indirect/inverse – when one variable is multiplied by a number and the other variable is divided by the same number i.e when one quantity increases, the other decreases. Likewise, when one quantity decreases, the other increases. (Klerk, 2007, p. 109 ) (Klerk, 2007, p. 104)

3. My new car has a fuel consumption rate of 7.5 L/100km. How much fuel will I need to travel 1456km? The previous model of the same car had a fuel consumption rate of 8.2 L/100km, which car is more economical to run? Step 5: Answer the question in a sentence. It will take 109.2 litres of fuel to travel 1456km.

4. Now try the Direct Proportion Worksheet and use the fuel consumption calculator as a checking tool. There is also a solutions page for you to check your working out.

6. Let’s look at an example: The time taken to complete a journey is inversely proportional to the speed travelled. A trip is completed in 2.5 hours when travelling at 65km per hour.

7. Continuing with the same data: The time taken to complete a journey is inversely proportional to the speed travelled. A trip is completed in 2.5 hours when travelling at 65km per hour. 4. Find the distance travelled in each case.

9. The data in the table below shows that the time taken to complete a journey of 650km decreases as the speed of the vehicle increases. Time (hrs)43.3321.6714.4410.838.677.226.195.42 Speed (km/hr)153045607590105120 If we were to plot this on a graph, it would look something like this:

10. Now try the Inverse Proportion Worksheet and use the fuel consumption calculator as a checking tool. There is an excel spreadsheet for you to use to check your graph in Question 3. A solutions page is provided for you to check your working out. This completes our lesson on Rate, Ratio and Proportion. There are more exercises on rate, ratio and proportion on the Test Yourself page.