You didn't include the options, so whichever one looks like x=(12.53+11.86)3.19 or something similar. You need to add the amount of gallons he bought, then multiply them by the cost per gallon, which will most likely be set equal to a variable.
Unfortunately, your problem statement appears to be incomplete. What distance are you talking about? Have you an illustration to share? How does 0.25 inches fit into this problem? Please try again. Double-check to ensure that you have shared all of the problem you wish to solve.
