Question

Efficiency of Machines Quick Check
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Question
Which car has the greatest efficiency?(1 point)
Responses

a 1,200 kg car that travels 20 km per liter of fuel
a 1,200 kg car that travels 20 km per liter of fuel

a 900 kg car that travels 20 km per liter of fuel
a 900 kg car that travels 20 km per liter of fuel

a 900 kg car that travels 15 km per liter of fuel
a 900 kg car that travels 15 km per liter of fuel

a 1,200 kg car that travels 15 km per liter of fuel

Answer 1

To determine which car has the greatest efficiency, we can look at the fuel efficiency in terms of distance traveled per weight of the car.

We have the following cars:

1. A 1,200 kg car that travels 20 km per liter of fuel.
2. A 900 kg car that travels 20 km per liter of fuel.
3. A 900 kg car that travels 15 km per liter of fuel.
4. A 1,200 kg car that travels 15 km per liter of fuel.

Let's calculate the efficiency (distance per weight) for each car:

1. **1,200 kg car (20 km/l)**:
Efficiency = 20 km / 1200 kg = 0.01667 km/kg

2. **900 kg car (20 km/l)**:
Efficiency = 20 km / 900 kg = 0.02222 km/kg

3. **900 kg car (15 km/l)**:
Efficiency = 15 km / 900 kg = 0.01667 km/kg

4. **1,200 kg car (15 km/l)**:
Efficiency = 15 km / 1200 kg = 0.0125 km/kg

Now, comparing the efficiencies:

- **1,200 kg car (20 km/l)**: 0.01667 km/kg
- **900 kg car (20 km/l)**: 0.02222 km/kg
- **900 kg car (15 km/l)**: 0.01667 km/kg
- **1,200 kg car (15 km/l)**: 0.0125 km/kg

The car with the greatest efficiency is the **900 kg car that travels 20 km per liter of fuel**.