To calculate how many miles it takes to get to your destination when driving at the speed limit with no stops or gas station breaks, you need to know the distance between your starting point and your destination.
Let's assume the distance between your starting point and destination is D miles, and the speed limit is S miles per hour.
The time it takes to travel D miles at the speed limit is given by:
Time (T) = Distance (D) / Speed (S)
Since we are assuming no stops or breaks, the time calculated above is the total travel time to the destination. The distance D is what you are trying to find.
If you provide the specific distance and speed limit, I can help you with the calculation.