Lesson 2
1. Lesson 2
1.6. Explore 3
Module 6: Proportional Reasoning
When comparing the fuel efficiency of two vehicles, the vehicle with the lower fuel-consumption rate will use less gas to drive the same distance. The vehicle will also go a further distance on less gas. If you are looking at the fuel-consumption ratings that use the rate of L/100 km, you want a lower value. If the comparison of miles per gallon is used, a higher rate is preferred because this means you can go a greater distance on less fuel.
In Try This 3 you used a graph to compare the fuel efficiency of two vehicles. Fuel efficiency can also be compared using unit rates.
Read “Example 3: Solving a problem involving rates” on pages 448 and 449 of your textbook. As you read over the example, think about the following:
To convert a rate that is
L/km to a rate expressed in L/100 km, multiply each term by 100. For example, 0.053 L/km is equivalent to 5.3 L/100 km.
- Which solution do you prefer: Katrina’s solution using a graph or Grant’s solution that uses unit rates?
- What are the advantages of using a graph?
- What are the advantages of using unit rates?
- Did the car achieve the manufacturer’s fuel consumption rating of 7.6 L/100 km on the first and/or second leg of the trip?
Self-Check 2
- Complete “Practising” questions 10 and 11 on page 451 of your textbook. Answer
- Complete “Closing” question 16 on page 453 of your textbook. Answer