Jillian and nikki each filled their cars with gasoline . the graphs below show the amount of gas in each car and the miles driven since filling blank

The total amount of gasoline each car tank can hold is shown on the left of each graph on the y-axis.

Jillian's car holds 22 gallons.
Nikki's car holds 20 gallons.
Jillian's car holds more gasoline.

Now we need to see which car gets better gas mileage. Getting better gas mileage means you can go farther with each gallon of gas.

With Jillian's car, after using 22 gallons of gas, you have gone 350 miles, and the gas tank is empty. 350 miles with 22 gallons is 350/22 = 15.9 miles per gallon.

With Nikki's car, you start with only 20 gallons. By the time you drive 350 miles, you still have some gas left. Not only did you start with less gas, 20 gal vs. 22 gal, but after driving the same distance, 350 miles, there is still some gas left in the tank, 6 gallons. That means Nikki's car used 20 - 6 = 14 gallons to drive 350 miles. 350/14 = 25 miles per gallon.

The more miles per gallon you get, the better the mileage is.
25 miles per gallon is better mileage than 15.9 miles per gallon.
Nikki's car has a smaller gas tank, but it gets better mileage.

Third Choice
Jillian's car holds more gasoline, but Nikki's car gets better gas mileage.

You are correct. Good job!