I would say between 10 - 17 miles per gallon
The 2013 Cadillac SRX gets about 17 miles per gallon in the city and 24 miles per gallon on the highway. This is an improvement over last years model which got 12 city MPG's and 18 highway MPG's.
The number of miles per gallon that the 1997 Cadillac DeVille can achieve is dependant on a number of factors such as the condition the vehicle is in or the driving style of the driver. However, the Cadillac DeVille is believed to get between 17 and 23 miles per gallon.
You can get 15 miles per gallon in city, 24 miles per gallon on the highway for 2009 model. On average, the Cadillac XLR will range from 20-30 miles per gallon. However, many things depend on the actual gas mileage. Road conditions, traffic, and speed limit will affect how many miles one gets from a gallon of gas.
17 City/26 Highway
30 gallon capacity tank in a 1999 cadillac escalade only 11 miles to the gallon city and 14 highway
49
17 city / 26-29 highway
16 -23 mpg
City-10-12 Highway-15-18
19 city 28 highway
My 2007 Honda Civic gets and average of 36-40 mpg or about 400 miles from one tank.