Fuel efficiency The dotplot shows the difference (Highway − City) in EPA mileage ratings, in miles per gallon (mpg) for each of 24 model year 2018 cars.

Part (a). Explain what the dot above −3 represents.

Part (b). What does the graph tell us about fuel economy in the city versus on the highway for these car models? Be specific.

The dotplot shows the difference (Highway − City) in EPA mileage ratings, in miles per gallon

The dots in the dotplot represent the difference between the highway and city EPA mileage ratings for a model year 2018 car.

The dot above-3 represents one model year 2018 car in which the city EPA mileage rating outperformed the highway EPA mileage rating by 3 mpg.

One model year 2018 vehicle's city EPA mileage rating exceeded the highway EPA mileage rating.

The dots in the dotplot represent the difference between the highway and city EPA mileage ratings for a model year 2018 car.

There is one dot above a negative integer, implying that one model year 2018 car has a city EPA mileage rating that exceeds the highway EPA mileage rating.

All other dots are greater than a positive integer, indicating that all other model year 2018 cars have a higher highway EPA mileage rating than a city EPA mileage rating.

As a result, we can see that the highway EPA mileage rating frequently exceeds the city EPA mileage rating.