I think it’s 3 over 7 I am rlly not sure if that’s right I just based it off the pattern
22.5 miles
You would create a proportion based on the given information, then cross multiply and solve for the number of miles 1 gallon of gas can go.
The common difference is 4. U know that the formula is the first term + d(n -1). N-1 is 14 so u know that 14 times a number needs to equal 56 because the first term is -3 and 56-3 is 53. 14 * 4 is 56. So the common difference is 4