C2.3 Estimate and report automobile-trip costs | Ontario Grade 11 Mathematics

Ontario Grade 11 Mathematics

Transportation and Travel

MEL3E specific expectation C2.3

A worker may need to estimate the cost of driving to a job site. A family may want to compare the cost of driving to an event. In both cases, a useful estimate depends on the distance, fuel information, and charges that belong to the trip. This lesson uses ordinary arithmetic with a calculator or spreadsheet. It focuses on estimating and reporting trip costs, not on predicting every possible cost of using a car.

What you will learn

Identify the information needed to estimate an automobile trip’s cost.
Estimate fuel use and fuel cost from distance, fuel consumption, and fuel price.
Include known trip charges, such as parking or tolls, when appropriate.
Report an estimate clearly, with units, assumptions, and a sensible level of precision.

1. Gather the trip information

Begin with the distance you plan to drive. For a trip there and back, use the total distance, not just the distance to the destination. Include the driving distance for planned stops when you can estimate it.

Next, find the vehicle’s fuel consumption. This tells you how many litres the vehicle uses to travel 100 kilometres. A vehicle information label, a recent record, or a reasonable estimate may provide this value. Fuel consumption can change with traffic, weather, load, and driving habits, so it is not a guarantee.

Find the fuel price in CAD per litre. Fuel prices can change, so note the price and date used. Also list known charges that belong to the trip, such as parking or a toll. Do not include a charge simply because it might happen. Identify uncertain costs as estimates, or leave them out and say they are not included.

Use the full planned distance, including the return trip.
Record fuel consumption in litres per 100 kilometres and fuel price in CAD per litre.
Separate known trip charges from fuel cost.

2. Estimate fuel use and fuel cost

The fuel-consumption rating gives a practical way to estimate how many litres the trip may use. Divide the trip distance by 100, then multiply by the vehicle’s litres-per-100-kilometres rating. This scales the fuel use to the length of the trip.

For example, a rating of 8 litres per 100 kilometres means about 8 litres for each 100 kilometres driven. After estimating the litres needed, multiply by the price per litre. The units help you check the calculation: litres multiplied by CAD per litre gives a cost in CAD.

A calculator works well for one estimate. A spreadsheet can help when comparing routes, vehicles, or fuel prices. Put the distance, fuel-consumption rating, and price in separate labelled cells. Calculate the litres first and then the fuel cost. Keeping the inputs visible makes it easier to find and correct a mistaken value.

To estimate litres, divide the distance in kilometres by 100 and multiply by the fuel-consumption rating in litres per 100 kilometres. Then multiply the estimated litres by the price per litre to estimate the fuel cost.

Estimate litres before calculating fuel cost.
Check that litres multiplied by CAD per litre gives a cost in CAD.
Keep input values and calculated values separate in a spreadsheet.

3. Add charges and report the estimate

After finding the fuel cost, add any known trip charges that belong in the estimate. Parking and tolls are examples. The result is an estimated total for the items you included. It may not be the complete cost of using a car; for example, the estimate may leave out unexpected detours or changes in fuel price.

A useful report states the trip purpose or route, total distance, fuel-consumption rating, fuel price used, and included charges. Give the estimated total in CAD. Rounding a money estimate to the nearest cent is often useful, but do not make it sound more exact than its inputs. If the distance or fuel consumption is approximate, say so.

Before sharing the result, review the arithmetic and assumptions. Check that you used the return distance for a round trip. Check that the price is per litre, not per tank. State whether parking or tolls are included. A clear report helps another person understand what the estimate covers.

\text{estimated trip cost}=\text{fuel cost}+\text{included trip charges}

Add only charges that are part of the trip and identify what is included.
Report the assumptions as well as the total.
Use the word estimated when inputs or driving conditions may vary.

A simple trip-cost record

Item	Example entry	Unit or note
Total distance	84	km, there and back
Fuel consumption	7.5	L per 100 km
Fuel price	CAD 1.60	per litre; note the date
Fuel estimate	CAD 10.08	estimated litres multiplied by price
Parking	CAD 8.00	known trip charge
Estimated total	CAD 18.08	fuel and parking included

Worked example

Example 1: Round trip to a training site

A worker drives 42 km each way to a training site. The car’s estimated fuel consumption is 7.5 L per 100 km. Fuel is CAD 1.60 per litre. Parking costs CAD 8.00. Estimate and report the trip cost.

Find the full distance
The worker drives there and back, so double the one-way distance. Using the full distance prevents the estimate from counting only half of the trip.
$42\times2=84\text{ km}$
Estimate fuel needed
The car uses about 7.5 litres for each 100 km. Scale that amount to the 84 km trip distance.
$\frac{84}{100}\times7.5=6.3\text{ L}$
Find fuel cost
Multiply the estimated litres by the price for one litre. The litre units cancel, leaving a cost in CAD.
$6.3\times1.60=10.08\text{ CAD}$
Add parking
Parking is a known charge for this trip, so add it to the fuel estimate.
$10.08+8.00=18.08\text{ CAD}$

Answer: The estimated round-trip cost is CAD 18.08, including fuel and parking.

Check: The distance is 84 km, less than one 100-km interval, so estimated fuel use should be less than 7.5 L. The result, 6.3 L, is reasonable. The report also states that parking is included.

Worked example

Example 2: Comparing two route estimates

A driver is comparing two routes for a work visit. Route A is 156 km in total and has a CAD 5.00 toll. Route B is 172 km in total and has no toll. The car uses an estimated 9.2 L per 100 km, and fuel is CAD 1.45 per litre. Estimate each route’s cost, then report which estimate is lower.

Estimate Route A fuel use
Use the route’s full distance with the fuel-consumption rating. The distance is already given as a total, so do not double it.
$\frac{156}{100}\times9.2=14.352\text{ L}$
Calculate Route A total
Multiply fuel use by the price per litre, then add the toll. Keep the calculator digits during the steps and round the final money amount to cents.
$14.352\times1.45+5.00=25.8104\text{ CAD}$
Estimate Route B fuel use
Apply the same vehicle rating to Route B’s total distance so both estimates use the same assumptions.
$\frac{172}{100}\times9.2=15.824\text{ L}$
Calculate Route B total
Route B has no toll, so its estimate is the fuel cost alone. Round the result to the nearest cent.
$15.824\times1.45=22.9448\text{ CAD}$

Answer: Route A is estimated at CAD 25.81, including its toll. Route B is estimated at CAD 22.94, with no toll included. Route B’s estimate is lower by CAD 2.87.

Check: Route B is longer, but Route A has a toll. Route A’s fuel cost is CAD 20.8104 before its toll, and Route B’s fuel cost is CAD 22.9448. After rounding each route’s total to cents, Route A is CAD 25.81 and Route B is CAD 22.94. Their rounded difference is CAD 2.87.

Common mistakes and how to avoid them

Using only the one-way distance for a round trip.

Correction: Calculate the there-and-back distance first, or state clearly that the estimate covers only one direction.

Multiplying distance by fuel price without estimating litres.

Correction: Use the vehicle’s litres-per-100-kilometres rating to estimate litres, then multiply by the price per litre.

Adding a toll or parking fee without saying it is included.

Correction: List each included charge and make clear what the total covers.

Rounding fuel use too early.

Correction: Keep calculator digits during the steps and round the final money estimate to cents.

Lesson summary

Gather the full trip distance, fuel-consumption rating, fuel price, and any known trip charges.
Estimate litres from the distance and the L-per-100-km rating, then multiply by the price per litre.
Add included charges and report the total with its assumptions and limits.

Check your understanding

Question 1

A car travels 120 km. Its estimated fuel consumption is 8 L per 100 km, and fuel costs CAD 1.50 per litre. There are no other charges. What is the estimated fuel cost?

CAD 12.00
CAD 14.40
CAD 18.00
CAD 144.00

Show answer and explanation

CAD 14.40

Estimated fuel use is 120 divided by 100, multiplied by 8, which is 9.6 L. Then 9.6 multiplied by CAD 1.50 per litre is CAD 14.40.

Question 2

A driver reports a fuel estimate and a known parking fee. What should the report do?

State the total and identify that parking is included.
Give the fuel total only and leave the parking fee unexplained.
Describe the estimate as exact even if the fuel price may change.
Add a possible toll without identifying it as uncertain.

Show answer and explanation

State the total and identify that parking is included.

A clear report names the included charges so the reader understands what the estimate covers.

Key terms

Fuel consumption: The amount of fuel a vehicle uses over a stated distance, often given in litres per 100 kilometres.
Trip charge: A known cost connected to a particular trip, such as a toll or parking fee.
Estimate: A calculated amount based on the information available; the actual cost may differ.

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About this lesson

Published by DoAssignment. This AI-assisted lesson follows Ontario Grade 11 Mathematics (MEL3E), expectation C2.3. It is a study resource, not an official curriculum publication.

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C2.3 · Estimate and report automobile-trip costs