Do you mean x amount of miles? if you do, you would add 3 because 3 is the amount of money that you have to pay no matter how far you go. You would get 1.75x because the number of miles you travel in the taxi, you would have to multiply that number by 1.75 to get the amount of money you would have to pay in addition to the 3 dollars that you would definitely have to pay.
